4 month old should eat every 3-4 hours. You mentioned sleeping for 10-12h and this sounds almost harmful for the baby. I don't think I'd like that.

Thanks for your recommendation anyway. I'm sure that there are many science-based techniques to "tame" children and make child care as atomic family bearable.

If you saw our baby, you wouldn't be worried at all that he's being underfed. Maybe the opposite. They'll want to eat every 3-4 hours during the day for sure; at night they can and do just sleep through it (same as me or you).

We didn't force anything or ignore him. And you don't have to believe me, but I'd encourage you to research more for yourself if waking up at night to feed a baby is something you're currently dealing with.