Meh. Advice I got from other parents or on parenting forums were those actually most likely to work.

What does not work is advice from "parenting experts" or doctor talking about non medicine etc. And of course advice people trade on forums non parenting forums (like HN) - too much of it is from people who don't interact with kids actually.

Quoted parenting experts are perhaps no use but actual experts are.

My mother was advised by the late great Hugh Jolly, a genuine expert.

If say don't ignore other parents advice, except the one I'm replying to. ;-)

I think it's reasonable to survey a dozen parents to get a bunch of different opinions and recommendations of what worked for others, so you have enough things to try if you got a situation, and don't just panic.

There are definitely a lot of families with sleep problems that could be solved if they read "Solve your child's sleep problem" by Richard Ferber (not just the famous two pages about baby sleep training). Many parents I talk to spend years dealing badly with sleep problems.

Not ignore, that's the other extreme. Take it with a grain of salt instead of as a bible. Experiment in a non-harmful way. Try things out, see what works. Every child is different, even from same gene pool.