Ask HN: What “tutorials” made you a better parent?

Most of us like improving in areas and skills that interest us - so we turn to books and tutorials.

I realised yesterday that I have never read a single book on parenting.

With my oldest daughter hitting puberty, that's long overdue. I _do_ like being a parent ;-) Time to improve!

What books / nuggets of wisdom really shaped the way you think about parenting, and/or made you a better parent?