3yo son suddenly tearful w lack of interest in everything & decreased appetite. could child so young be depressed? never been like this before...

YES: A 3 year old can be depressed. Look for changes in the environment - family fights, loss, absent parent, witnessing an accident, etc, things that would threaten a young child. Give the pediatrician a look too to rule out physical problems.

Childhood Depression: Yes a three year old could be suffering from a low mood. Consult with your pediatrician for advice and ask if a referral to a child psychologist if his l low mood persists. Best wishes.