Can a 3 year old take melatonin to help sleeping schedule at night?

Sleep habits first: Sleep is a learned behavior to an extent, and kids learn by association. Make sure your child goes to bed in his own bed and space at the same time at night, and get him up at the same time every morning. Set clear expectations on what you want him to do and have a routine. Turn electronics off and dim lights 45 min prior to sleep. Avoid late naps.

I never suggest it: There are no studies that would verify the safety of this product or define a dosing level in young kids.