
There is no single cause of depression in children, but experts say the illness often runs in the family. Other factors that may trigger depression include stressful life events, long-term use of some medications and chronic illnesses.
Depression is often difficult to diagnose in children, experts say, because some of the behaviors associated with depression can be normal patterns of behavior in a growing child. Researchers say some of the signs of depression in adolescents and children include sadness that won't go away and a decreased interest in playing or involvement in favorite activities. If your child is moody, irritable or has suicidal thoughts, those are serious signs that you should pay close attention to--especially if those types of behavior last for long periods.