Newborn babies don’t yet have a sense of day and night. They wake often to eat – no matter what time it is.| kidshealth.org
School-age kids need 9–12 hours of sleep a night. If they don't get it, they may be cranky or moody, hyper, and have behavior problems.| kidshealth.org
Preschoolers sleep about 10 to 13 hours during each 24-hour period, and it's important to help them develop good habits for getting to sleep.| kidshealth.org