My son will be a year in 2 weeks and still doesn't sleep through the night with or without cereal, every now and then he'll sleep for 4-5 hours at night and that started at about 6 months
My 4 week old daughter did once out of the hospital, I'm sure she would have even there but they woke up up alot as hospitals do (knock on wood as I know there is a 4 month sleep regression lol). My first child didn't until 6 months and my second not until after a year
Im pretty sure its because the minute he cries during the night his dad gives him a bottle. I told him we need to let him cry it out he isnt hungry he just wants a bottle since he so use it.