My kids get up with the sun regardless of when they go to bed, but if they're not in bed before about 9 they'll be cranky when they get up, especially in the summer.

With one kid it isn't too bad, but when you have multiple kids they tend to be up with whomever is the earliest riser, because they make a lot of noise when they get up and wake everybody else.

At the risk of inexpertly offering bad advice, you could try blackout curtains?

I'm 33, definitely more of a night owl but if it's sunny out I'm pretty likely to be wide awake at 6am after going to bed at 1. Black out curtains made all the difference for me.

The kids don't even like having the regular curtains closed. Besides, having them used to getting up early is good when school is in session.

Our baby goes to sleep between 5-8pm and sleeps until 6-7am.. She makes the rules though, when she finally becomes grumpy in the evening I prepare some food and it's off to bed. Works every time!

I believe all babies are different, so luckily our first have been kind to us this far with her sleeping habits and mood.

My 1 year old went to bed at 11pm and just got up today at 8AM. We are cosleeping, so our habits matter a lot, but he just likes to stay up later and we haven’t been able to push his bedtime earlier (and if he doesn’t get his 3 hour nap in the afternoon, god help us. I’m not too worried about it.

I had the same experience as you.

My hypothesis is that all the nonsense about kids needing 12 hours of sleep/"more than adults"/early bedtime is just that, started by parents who wanted some time to themselves at night and perpetuated through convention.

Our kids started sleeping, waking up and generally behaving better once we stopped enforcing arbitrary bedtimes.