Mental health is pretty important since it includes our emotional, psychological, and social well being. It also affects how we act, think, and feel. It also determines how we make choices and how we can relate to others
A major side effect that stress can cause on the gastrointestinal
system is diarrhea. It increases the acid in the stomach and the mill of the
stomach to shut down making you feel nauseous. Stress can cause your colon to
react in an absurd way that gives way to diarrhea or constipation.
You should comfort him, and ask him what's wrong. Treat him like any other person and try to find a solution to his problem. Be there for him so it makes him happy again :)