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I've never seen a graphical abstract like this before, what a fantastic idea.
I think most experienced child-carers could tell you this, but it's great to see it made explicit.

I personally favor a bounce->rock->walk->sit pipeline, but ymmv based on the temperament of the child.

As the parent of a 6.5 month old, this is very interesting.

We had figured out that once she falls asleep, we wait 8-10 minutes for her to get really deeply asleep before putting her down. But the transport to calm crying, that is really going to come in handy.

As a parent of a 5mo old I had to discover this on my own. Luckily my daughter makes it abundantly clear that she does not like me to sit while I hold her. Our midwife even said that babies like to know you are up and ready to escape predators. Not sure how true that part is.
I think of it as a fitness measure: Are you active enough at moving towards food gathering sites, preparing and surveying the landscape, creating and fine tuning your tools? If it is an approval of sorts on behalf of the child, then it also points to some really basic learning that is beginning to flow between the parent and child
That's a mind-boggling theory actually, that some general survival skills are encoded in the parent-child relationship. Basically you have to become a parent to level-up your survival skills.

I wouldn't put it past evolution to encode useful information wherever possible, but it would be hard to prove that theory.

I thought it was just my kids. We like to think of them as requiring "the path of greatest effort"
Not clear whether evolution would select for crying in the possible presence of predators (so fighting adults can be woken) or for silence (to avoid attracting attention as prey).
I think babies cry when they get tired to warn parents they are going to fall asleep soon, so that parents know they have to take them somewhere safe to sleep.
"You cannot sleep while enemies are nearby"
Crying garners attention from adults in either case. Any attention could be better than no attention I suppose.
Use the hairdryer. It works like wonders.
I put my infant in a carrier in front of the washing machine and dryer a couple of times. It was great!
Cutting edge research indeed. We need to spread the news, tell all the parents that carrying kids helps sooth them. There is no way that parents could have come up and tried this on their own.
I also find it hilarious when studies point out the blatantly obvious - but I'd rather see this way more often than tons of unreplicable crap churned out.
I independently found my way to a similar approach. However, having resources available to new parents is immensely valuable when you're at your wits end.

Actually, you could say the same about all manners of recording history; Story telling, art, education, music.

Why bother with any of it if people can figure it out for themselves? Because we progress further when we work as a team and share knowledge.

To be fair, some of us (me included) are about to be parents for the first time. I'll take all the good pointers I can get, obvious or not.
Don’t worry, this one will come up naturally.

In general, I recommend taking all advice with a grain of salt: not because it is bad advice, but because no kids are the same, and what works with one will not necessarily work with another. Just take it easy and try to not worry too much. The unbroken chain of your ancestors have all figured it out, and so can you. And congratulations!

And, what works on one kid one day, may not work the next!
Yeah as someone else said, you will figure this out. There's only so many things you can do with a crying baby. It's completely natural that you will walk and hold them and figure out a rhythm. I've figured out with my second that lighting levels are important. Timing the darkness works well, and I figured it out by walking around with her but the lighting is really variable in my house and going too light or too dark will startle her. Probably could do a study on hoe gradual shifting of lights effects baby.
That wasn't the point. The point was that you don't go from walking the baby to sleep to putting the baby down horizontally. You sit down for 5-8 minutes first, during which time the baby transitions into a deeper sleep that won't be disturbed by being laid down.

If you go from walking to putting the baby down horizontally, the baby will often be awakened by the sensation of falling backwards, and wake up.

That's hardly a nontrivial thing to try, and indeed, I came up with this genius idea independently. Should have published it!

Do you have children of your own?

I do. No one is saying "no parent has ever tried this genius idea". They're just saying that it's useful to have a study on it, and parameters around how long one should remain sitting before attempting to lay the baby down. Also, you're moving the goalposts. Your original comment said derided the idea about walking a baby to sleep. But that shows you missed the point of the study, which was not about walking at all, but rather the next step.

That step is apparently not super obvious because this grabbed over 300 upvotes on HN, no small feat.

Even if it was obvious to some, parents of newborns are often (always?) sleep-deprived, so it might be hard for them to remember how well it worked to hold the baby still for 2, 4, or 6 minutes. I didn't have especially difficult sleepers, but it would have been nice to have seen this data back when we had tiny ones.

I try to recommend to new parents to get a big room air purifier to clean the air where the baby sleeps but also to add a nice low bass noise (from the motor) that you can’t get from a white noise generator. Our filtrete has been running non-stop for 11 years (kind of crazy).

Definitely helps keep them asleep and non sensitive to sudden noises in town/city.

Long term exposure to constant droning sounds could cause issues in language centers of the brain.

When we rely on sounds for kids, we stick to sounds that mimic the more random/non-droning sounds you encounter in nature. Birds chirping in a forest, evening crickets and frogs etc.

> Long term exposure to constant droning sounds could cause issues in language centers of the brain.

Do you have a source for this? We've always used white noise.

They may be citing a study that circulated recently about how white noise is the reason why we have an autism epidemic. I can't seem to find the study, though. But I do remember laughing.
No.
Cool. I hadn’t read the study you linked. Thanks for sharing.
Slightly pedantic: I doubt you use white noise. White noise is extremely jarring.

You probably use brown noise or so?

Anecdotal but I used a noise machine that played brown noise because I was informed it mimics the sound of the baby’s womb. My daughter is extremely advanced in all areas of learning now at 5 years old. Her first word was hi at 4 months.
Imagine what my conversationally advanced 4 year old would be capable of if only I didn’t use that darn noise machine all the time!
So much effort just to get kids to do something completely natural. This explains why Western adults are so malfunctioning.
I think it's more an indication of higher expectations in child-rearing. If you're struggling daily for survival and 7/10 of your children will die before age 6 I don't think can afford to spend hours every day experimenting which method will get your child to fall asleep without crying.
Except children in traditional societies demonstrably cry less and are happier (both parents and children). Anybody who has spent time living in traditional societies vs living in the West see the differences - chiefly, the sheer anxiety that western children are introduced to from the first day they step foot in the world.
Doesn't surprise me that people in a society that values individual liberty develop more anxiety as they are expected to take responsibility for their own decisions,

as opposed to a society where traditional authority commands you exactly what to do and you'll obey or else.

I found this out by just trial and error.

Hold and walk until they sleep, then keep walking for 5-10 minutes, or just sit down for 10 minutes before laying them on the bed.

> It should be noted that, unlike most behavioral interventions for infant sleep difficulties, 9,10 this protocol does not address any long-term improvement of sleep regulation.

I'd expect as much since this is the first thing a parent tries to do. Holding the baby when they wake crying several times a night will calm them, not exactly revelatory, but can come in handy even for more lasting solutions.

I find the lit/consultants have wildly varying degrees of severity for approaches, including for gradual extinction. The mistake I think we made prior to seeking intervention is feeding-to-sleep for too long, i.e. the baby would drink a bottle right before bed and get knocked out (mostly). They were always accustomed to being asleep in arms before being put down. I think if you feed slightly earlier in the routine-chain, with the lights on, you go a long ways to avoiding this issue, since you can rock them while they're awake for a time before putting them down. In some branded variants of graduated extinction, they suggest making sure your baby is super wakeful and basically dropping them in the crib right away after reading a book - this seems needlessly harsh when going from the opposite extreme, which is reflected in the baby's level of crying. We found that it went well to rock them until they were calm and drowsy (but still awake) before putting them down. The protest was mild and short-lived, but of course that's only our experience.

This. Be very careful implementing this paper's technique. It does NOT promote long-term sleep independence, which should be the goal. Crying before sleeping is not inherently bad. The objective function is not to greedily minimize crying. If you are interested in materials on sleep training, I recommend taking a more holistic view than a single paper. "Healthy Sleep Habits, Happy Child" is a good reference.
I found that a SNOO was very effective in the first 6 months. It is expensive, but it was way better than being even more sleep deprived. It plays white noise and rocks the baby if it senses them stirring. https://www.happiestbaby.com/
For those who intend to have one child only, they now have a rental program where they ship you the SNOO, you use it up to 6 months, and ship it back. Works out to about the same as what you'd lose by buying it new and reselling it at the end. Highly recommended!
Ok this we figured out.

What I need to find out is what to do in the car. Our kid mostly calms down while walking, but unlike his older brother the car vibrations do not make him sleep at all. And so once he starts crying in the car, we have no way of calming him down, beside stopping the car and carrying him.

It seems like very bouncy driving (a sequence of high acceleration followed by sudden braking) helps, but it’s kind of wreckless, makes my wife sick and my older kid angry.

Help!

Probably just need to gut it out for a couple road trips and try not to show the kid how stressed out you are while it’s happening - kinda like a thunderstorm. It gets better. Good luck.

Intermediate tactics: white noise in the back seat, maybe some lullabies, singalongs, make sure the seatbelts aren’t too tight, maybe a drink or pacifier, etc - whatever to keep things quiet for a bit.

I got nothing. For us, we discovered that if we time car trips around their bedtime or naptime, she cries a while and then conks out. Then when we reach our destination, we take her out and put her in an adjustable lay-flat stroller (if outside) or to bed (if home). The process of getting her to conk out while we drive? Just pure grit, endurance, and lots of singing lullabies, which may simply be correlated, rather than causative. Sometimes it takes a while. :(
If their car seat is rear facing, do they have one of those mirrors on the adult seat, so they can see what's happening/see you?
This made a huge difference for us when Gjcp_v2.0 was small enough to be in a rear-facing car seat.

You can see them, they can see you.

More evidence on how harmful a car-centric lifestyle is to humanity.
Your virtue has been signaled. Pretending cars are going away is not a realistic view.
Please explain? I don't see how one particular baby's dislike show anything about whether it's harmful.
More evidence of how anti-car fetishists are ruining HN
If you were aware of how many things make babies cry I think you would be quite embarrassed about this comment
Child safety and cars sure is related - and history buffs will be glad to know the “kindermoord” of automobiles was what got the Netherlands to change from car-centric cities with many lanes wide traffic jams, to the best city infrastructure in the world

https://usa.streetsblog.org/2013/02/20/the-origins-of-hollan...

Cars produce crazy noise pollution, and car lifestyle requires massive subsidies such as street parking, and a huge share of city real estate being used for parking and roads.

Lately, I’ve been inspired by this channel “Not just bikes” on the subject, and other HN readers may find it interesting as well https://youtu.be/XfQUOHlAocY

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I wonder if the reason babies cry so often is because they are "supposed" to be carried by their mother constantly in a hunter-gatherer setting.
They're supposed to be nursing... I don't know why people are being weird and complicated about this. If the baby is crying, breastfeed.
1.) Some women will never produce milk in sufficient quantities after the child is born, just due to random luck.

1a.) Formula is expensive, takes minutes of effort to prepare, and not always obtainable.

2.) Too much of a good thing is a bad thing. Comfort nursing at certain stages of the child's life will end up sleep training them in a negative way.

3.) Some babies are born with impairments that do not allow them to nurse effectively, or at all.

4.) Moms need a break from nursing too.

Tell me you’re not a parent without telling me you’re not a parent.

Babies cry for very few reasons, and reason number one, two, and three, is hunger.

Depends on age.

When teething number one two and three are teeth.

Teething is miserable no doubt, going through it now. My comment assumed we were talking children who were not yet teething. Possibly a bad assumption on my part.
I've had a colicky baby who cried not because he wanted to nurse (he would stop wanting to nurse after a certain point) and not because he was hungry. There are a certain percentage of babies with colic, we don't know why they cry but they cry and carrying them, nursing them, feeding them breastmilk through a bottle doesn't really help.

Then for our son, it grew less and by the time he was 3 months old, he was a very happy baby.

> Teething is miserable no doubt, going through it now.

What took you so long to start teething?

come to our house between 22 and 01 AM and I’ll show you a baby whose intense crying is inconsolable by breastfeeding
Hold him, breastfeed him and co-sleep with him and he'll be fine. Otherwise you're doing something wrong.

It's basic common sense, if babies evolved to scream for no reason for long hours in the wild, early humans would have been killed off by nocturnal predators ages ago.

> Hold him, breastfeed him and co-sleep with him and he'll be fine. Otherwise you're doing something wrong.

Some humility would serve you well.

Some babies, even toddlers, scream loudly for extended periods with no way to console them. Our neighbor a decade ago had one such child. They were great, loving parents. The kid was obviously happy and content. Yet, every night, for several hours, she was a siren. They saw lots of doctors. They started with co-sleeping, for what it's worth. In the end, a separate bed and a parent reading a book with ear plugs [for several hours] seemed to cause the child the least distress.

When the child was 2, and still screaming, a new neighbor moved in. They spread neighborhood gossip of child abuse. They called the police and child protective services. Luckily, their case was so well documented, it was not an issue. The issue was "resolved" with better soundproofing.

The kid is a teen now. Extremely kind, well adjusted, helpful, smart, and, a sound sleeper. She's obviously loved very much her entire life. I think the parents did a great job.

My point still stands. Behind many a crackpot on Kensington Ave are well-meaning "good" Parents.

Shrieking children for hours is very much a modern phenomenon.

”It has been an age-old practice to drug crying infants. During the second century AD, the Greek physician Galen prescribed opium to calm fussy babies, and during the Middle Ages in Europe, mothers and wet nurses smeared their nipples with opium lotions before each feeding. Alcohol was also commonly given to infants.”

yeah it’s a modern phenomenon because overzealous regulatory agencies gatekeep parents’ access to opium lotions

If supply is low, you can still comfort nurse and supplement with formula to make sure they actually get enough nutrition.
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There are lots of babies who can’t breastfeed efficiently unfortunately.

They slowly run out of energy while trying to suck and you only realize in horror when they don’t wake up from their hypoglycaemic “nap” by themselves anymore.

Breastfeeding is a wonderful thing and it’s an important default more mothers should be able to practice for as long as they and their child need and want to.

It’s also a highly complex process that often even a lactation consultant won’t be able to “fix”.

So yeah no shame, just empathy for all involved.

Feeding suddenly gets 1000x harder especially when deciding to go down the commendable road of pumping. All while potentially suffering from additional knock-on effects from lack of often very effective comforting-through-breastfeeding for example.

Even if health, general well-being and circumstances allow getting breast milk into a baby over even just the minimally recommended time can be one of the hardest things you’ll ever witness your partner go through.

For the lucky - majority I’m hoping - it can be both very fulfilling and sensual bonding probably even relaxing to the mother as well.

Be very thankful if that’s so in your case.

Your statement is so absurd that the only explanation is that you must not have had children. Hunger is only 1 of a dozen different reasons why babies will cry.
To be fair, giving them a boob does often comfort them, even if it's not hunger or thirst.

The advice is still not generally applicable.

(About half the parents in the world, fathers, aren't even capable of producing milk.)

This may have worked for you, but I've seen babies cry after breastfeeding and burping. I've seen parents try to force them to breast feed and they bob on and off because they just aren't hungry.

The breastfeed strategy worked probably less than half the time for my oldest.

I'm glad this works / worked for you. If only it were this simple for the rest of us!

Someone who has never seen a breast after feeding the babies that bite for long, and never known the pain when babies suck the hurt nipple.. Yes, we all would like to breastfeed the babies and keep them calm forever. (I am a father of twins)
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Probably it’s because their whole body is in pain, since all of the sensors are not fully calibrated yet.

We are constantly in pain, it’s just that we have calibrated our brains to ignore specific levels of pain or cut off completely sensors.

Typical example of signal we filter out is the sense of our organs moving inside our body.

They're also... growing fast. That probably hurts...
I've referred to the first 3 years as a slow-motion hulk morph of stretchiness.

Hulk is grimacing for a reason ;)

I have never heard of this. Seems like you're suggesting that it is possible to recalibrate the brain to ignore pain - like a toothache, for example?
I think this is why doctors consider chronic pain kind of not a thing. We are supposed to recalibrate. But I'm personally pretty sure this is nonsense and they have convinced themselves this is true so they don't have to feel bad about withholding powerful painkillers due to society disapproving of them.
I guess oscillating pain is also "chronic pain" and you want calibrate for that.
This sounds pretty fanciful and ungrounded. In general doctors don't "consider chronic pain kind of not a thing". I have chronic pain, I see doctors about it, and none have ever expressed any doubt. Quite the opposite: some of the doctors are chronic pain specialists. There are pain management centres at hospitals to help people with it, and they prescribe "powerful painkillers" if they're useful, but they often just aren't (e.g. for me).
> Probably it’s because their whole body is in pain, since all of the sensors are not fully calibrated yet.

Anyone have a source for this? It sounds really interesting, but never heard anything like it.

> We are constantly in pain, it’s just that we have calibrated our brains to ignore specific levels of pain or cut off completely sensors.

> Typical example of signal we filter out is the sense of our organs moving inside our body.

Interesting, do you have a source for this? Would love to read more.

I remember running into this idea when I was taking care of a colicky infant. Baby carrying slings and wraps seemed very popular among new parents. This article covers some of the evidence: https://www.theguardian.com/lifeandstyle/2005/jun/08/familya...

In my experience, baby carrying is great but some babies just cry. My first child was held constantly, and we spent every evening bouncing hard on a yoga ball with her, but it wasn't enough to fully quell the crying.

Baby sling / baby carrier is just miraculous. First daughter with second wife was crying a lot and we had to carry her much. With the sling you can basically carry the baby and still have the hands free and keep on with your stuff.

You also have to learn to recognize the stages of sleep. Hold the arm of the baby up and down. If the arm remains in the air, this is light sleep. If the arm feels heavier and goes down all the way, this is deep sleep. Only then put the baby into the cot. This is quite important to know.

Some babies still cry even if carried all the time;

But there is an issue in our society that if you are looking after a baby by yourselves during the day, so nobody to hand them to, you do need to put them down briefly for practical reasons.

Some more important conditions from the method used:

> Experimental sessions started approximately 1 to 2 hours after the last feeding

> In most cases when mothers laid the infant down, mothers held the infant with one hand behind the neck and shoulders, and the other hand under the buttocks or thighs. The mother laid the infant on its back in 18/19 samples of the 1-month-old and older infants, and 7/7 of the neonate samples, whereas one infant was laid with a sideways landing, later to be turned on its back.

>To examine the effect of sleep duration on the sleep/wake outcome, the interval between the initiations of infant sleep and laydown was calculated. The timing of the infants’ sleep onset was defined as the initiation of the behavioral sleep state, satisfying both of eye closure and no vocalization.

> Waiting 5 to 8 minutes before laydown prevents infant awakening

LOL. Definitely did not work on my (now 3 year old) daughter during the infant phase.

Same. I personally found it very difficult to tell the difference between actually asleep vs. starting to fall asleep.
I use the paci as a cue. Once it falls out of their mouth, they're usually asleep. (Usually...)
None of my kids would ever even take a pacifier. There are so many different babies that there is certainly no one true method.
Absolutely agree. Every baby is different. Took a couple months for my last one to take a paci because he had a small tongue tie that we had to work through.
That's the number one thing about all these advice articles. Every kid is different. That's great to have tips of things to try, but there's absolutely no secret formula and 4 kids is a really small sample size.
I have twins, they share a room. they are 19 months old. They have been sleeping through the night since 10 months old. My technique is I put them to bed fully awake at the same time every night. They each get a half full bottle, and I say good night. Before I goto bed, I put another half full bottle in their cribs, and they find it on their own when they wake up. And then I see them in the morning. I had to let them cry it out for a few weeks, but now they just goto bed with no crying. In the morning they talk to each other until I go into the room.

I couldn't imagine doing it any other way. too exhausting for everybody. Being able to goto sleep on your own is a skill! And it's a self taught thing.

> In the morning they talk to each other until I go into the room.

Brings a tear to the eye.

I think (because I have no experience) twins must have a deeper human connection than non-twins, and if so, I wonder if can / is applied to other relationships. I wonder if there's any vestigial evolutionary benefit.

Semi-related funny story: When our second was old enough to go into a cot, rather than a bassinette, we tried putting both the kids into the same room when they slept. It was fine... for the few minutes it took for the youngest to realise that there was "someone else" in her room, and started scream-crying, which woke up and set-off the eldest into scream-crying.

We thought the fucking room must have been on fire or something, never moved so fast in unison with my wife before or since. It was existential dread at the time. It's hilarious now.

(It really was just that the youngest wasn't used to having the eldest also in the room, it worked fine together for a few years after that until they eventually wanted their own rooms - between times, however, they were actually comforted by having each other in the same room - also brings a tear to my eye.)

> I think (because I have no experience) twins must have a deeper human connection

For all its worth, I know at least 2 pairs of twins who cannot stand each other.

Definitely an addition to the collection of anecdotes.

My dad is an identical twin, and I get along with my cousins from his twin brother better than my other cousins. There's a gender / age difference with the other cousins though, so may not count for much.

Further question to the ether: Do identical twins get along better than non-identical twins?

No judgement here, but I think I can hear a pediatric dentist down the street streaming some obscenities of some sort.
No one’s mentioned the Ferber method yet, it’s what got my daughter to start falling asleep on her own and do full nights at 5 months old. Took about 4 nights.

https://en.wikipedia.org/wiki/Ferber_method

This is an excellent method. Our first kid was very difficult, but that changed after learning the Ferber technique. We've used it with subsequent children with great success.
We’re 3 kids into a “softer” version of the Ferber method and also report that it works well.
Same here we transitioned at 8 months old from sleeping in our room in a side sleeper to sleeping in his own room on his own bed by using the Ferber method, it worked great.

We did soften it somewhat by setting the maximum interval at 7 minutes (we couldn't stand longer than that). It might have slightly reduced how quickly the method works (although we started to really see great progress 4 days in which is in line with the book).v

This was called "controlled crying" when we did it, and it worked a treat on our first and, as far as I can recall, wasn't necessary for our second (yes, lucky!). It was surprisingly quickly effective, maybe a week. Recommended.

I do remember that quite sharp 'parental pain' (it's hard to describe, it's like an intrinsic 'hunger to help') of knowing that we have to get through the next X minutes of baby crying without going in there. It's good to have a supportive partner so you can both keep each other in check (or to put it how I'd prefer: "well, we're both bad parents if this doesn't work, it's not just me").

I personally disagree with this. I think that instinct is very meaningful and valid, and most people would be better off co-sleeping with their children rather than teaching them how to be alone more effectively when they’re too young to have done so in the wild.
i don't know if we were just lucky, but co-sleeping worked very well for us.
This works with our boy. We have a bedside digital clock, and I've found he requires 5-7 additional minutes after he closes his eyes and appears to be asleep before I can put him down. Any earlier and he'll wake up and cry.
There's so much snark here but I love this. I'd take reading papers like this over mommy blogs every day of the week, even if it's to state the ostensibly obvious.

Does anyone have any other interesting child-rearing resources in this style?

From time to time i go through this cdc[1] website. It is quite comprehensive on child rearing tips.

For a longer form reading i went through [2] and still visit it from time to time. I like it because it discusses multiple approaches and methods and discusses what works and what does not. A bit more scientific, but the gist of it is that most of children's behavior problems are actually parenting problems.

Recently I was trying to figure out why my 1,5 years boy had more liquid poop only when he was in the kindergarten. This made him need to be home quite often. Turned out they were giving him some drink with fruit that made him drink too much water. Given that children do not have perfectly function water absorption in the colon if they drink too much, their stool gets more liquefied. The liquefied poop gets confused for viral diarrhea and he then needs to stay home. I got that insight from [3]. After resumption of diet and removal of sugary fruit from the water, he has been fine for a while now.

[1] https://www.cdc.gov/parents/essentials/index.html [2] https://www.ncbi.nlm.nih.gov/books/NBK402020/ [3] https://adc.bmj.com/content/79/1/2

Sugary drinks for 1.5 year olds, at kindergarten? Capri-Sun and the like should be banned in schools and daycare, people don’t realize it’s not that different from giving their children Coca-Cola every day.
GP didn't say sugary drinks, but rather water with sugary fruit (all fruit is sugary). Big difference!
The exact opposite.

Most published research is bogus. Not everything is physics or chemistry. Most things are actually not.

I'd rather advice based on extensive experience and wisdom than "research shows that ...". Basically everytime I see someone says "research shows" I mentally mark it as bullshit.

You’re in the wrong forum buddy. Pink colored antivax pages may be found in Facebook.
What is this, red herring, ad hominom, and straw man, all in one sentence?

It's well established that most published research in Psychology and Sociology does not replicate. So there's that. If you don't want to accept that, maybe you are the one who belongs on a facebook page?

ran out of Latin terms? I didn’t start the overt generalization in the conversation to be exact.
What about advice based on the extensive experience and wisdom of researchers?
Papers are great, but the fact that this is still a topic of discussion in the 21st century shows that there are no magic bullets, and putting too much stock in a techniques can feel as bad as the problem you are trying to solve if they don't work and you blame yourself.

Among any parenting peer group there will be some whose children fall asleep instantly with no intervention and some who spend hours doing bedtime and get woken up dozens of times a night, despite doing more or less the same thing.

Very much this. I do like that they split the children into "crying-start", "alert-start" and "asleep-start" groups, but ultimately I have had the experience that every kid is different and sleeps differently.
The books by Emily Oster are great, they’re purely based on data and she’s a PhD in Econ at Brown so she knows to not misinterpret. She’s also a mother and blends in just enough personal experience into these books to make pleasant to read while never straying from the aim of scientific accuracy. On many topics the answer is unfortunately still “some studies show X but there are flaws or they aren’t statistically significant so we don’t know for sure what Is the best answer”
Just a random tip: noise canceling headphones, particularly over-the-ear, are great for keeping calm while holding a screaming baby. They can scream quite loudly, and when you hold them they are often right next to your ear!
Just tried this on my newborn and it seemed to work! I know there are folks saying this isn’t a new finding but i find the timings really helpful. Previously I was walking the baby too long which was wearing me out but having research based timing advise helps a lot.
It only works, if it consistently works. And it only doesn't work, if you tried it consistently and it didn't work.
That's not even close to true. Things can work well at first and then stop working after a while. That doesn't mean it didn't work initially.

If we only prescribed pain medication based on your definition, practically none of them would make it through.

Your body adapts to its environment and as such very few things will work in perpetuity.

Bumbing the baby in the cart over a threshold worked very very well initially, for like 3 months, and suddenly stopped working at all.

I feel a great deal of confusion is stemming from that advice might come to late or to early in the childs life.

I'm pretty sure our 4 day old will react exactly the same way to this as he does when we put him into the next to me cot straight after a feed. Which is to say he'll sleep for 2-5 minutes, realise he's further away from the breast than he wanted to be and wake up.

What works for us and our previous child is cosleeping. After I saw both my partner and our eldest fall asleep simultaneously after finishing a feed I became a convert.

For a lot of parents, cosleeping is effective in the short term but counterproductive in the longer term.

Also, it's a SIDS risk.

When controlled for alcohol and drug use it's actually pretty a pretty insignificant risk. 50% of families admit to cosleeping in the UK, I suspect that's likely to suffer significant under reporting.

I think it's far better to do it deliberately, knowing where the baby is and deliberately positioning to avoid the possibility of rolling towards them, than to do it via exhaustion at 4am.

And our 3 year old coslept until 6 months and has slept 8pm to 8am in her own bed ever since so if that's counter productive I'll take it.

Congrats! I’ll have my third in the next 2 weeks.

We noticed the same thing with my first 2 kids. They’d wake up from a dead sleep after putting them down. Once my second child was 3-4 months old we would let him cry for about 1 minute and found he usually went to back to sleep. Worked well. With my first we would run in immediately and I still think she has going to sleep issues.

I must be lucky. Our new born is out after a few minutes on the pacifier. Normally out until we wake him for the next feed.
Sleep on a human being for the first year was the only solution for us
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Just remember holding my kids, walking, sitting, and counting to 100 one or more times, and then gently laying them down. Those nights of counting.
I did something similar but then I had to press my hand on his back or butt so he felt like he was still being held, then count to 100 and release it as slowly as possible.

Babies are ridiculous.

Watch out for tongue tie: if the connective tissue that's right underneath the tongue goes too far forward, it can make it so the baby can't breath normally through their nose when on their back. If your baby sleeps with their mouth open, that's a sign. Our baby had this and couldn't sleep on her back until we got it fixed. I am not a doctor—talk to someone competent first!
And the fix is pretty straightforward, at least for us. Dr snipped and applied pressure, baby seemed to not be in too much discomfort. In and out.
Tongue and mouth ties can also impact breastfeeding. Def something to be aware of!
Tongue tie is so heavily over-diagnosed and even treated right now. Just an aside to those in the thread, get a diagnosis from a pediatric dentist or other doctor, not a lactation consultant and not from the doctor that is responsible for doing the revision.
This might depend on where you are. If you're from the UK, the only way of getting this diagnosed within any reasonable time frame is a lactation consultant. Most NHS staff is not trained to diagnose tongue tie, which is not surprising given their historical roots.

Tongue tie was quite obvious for my first daughter (it even runs in my family), but hospital staff still refused to do a proper diagnosis and said it was fine. It was not, and impacted the breastfeeding.

What are the percentages? What's the correct rate and the false positive diagnosis rate?

Or are you just anecdoting?

It is a complex issue. Tongue tie is a real thing that causes real problems and lack of a diagnosis can lead to a lot of unneeded suffering and distress. Compounding this pediatricians are often not very responsive to breastfeeding concerns.

However, the placebo effect here is really strong. Firstly because tongue tie revisions are to fix issues that very often are the kind of thing that resolves on it's own. Secondly because parents are told they will see some sort of fix and they are putting their child through a procedure than can be painful so they will really want to see an improvement.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5804819/

"A desire to increase rates of breast feeding initiation and absence of standardized criteria for the diagnosis of ankyloglossia have resulted in runaway rates of frenotomy for newborn infants in some parts of Canada."

https://internationalbreastfeedingjournal.biomedcentral.com/...

You'll see a really unfortunate statement like this in almost every article discussing the issue "Randomized controlled trials of optimized lactation support vs. frenotomy and of scissors vs laser in performance of frenotomy are needed."

https://undark.org/2021/05/26/hidden-tongue-ties/

Dad on my 3rd baby (2 months old now). I'm like a WWE ref, I lift up my son's arm to check if it drops without resistance, after walking/dancing for a few minutes. Then fast to his bed if so.