Depression is a complicated illness/disorder.
Sometimes it is characterized by huge mood swings such as for someone with Bi-Polar or Manic Depression
Sometimes it can be a so called low grade chronic depression which is called Dysthymia, or a chronic Major Depression.
Sometimes it can be caused primarily by a chemical imbalance and sometime by stress and more often a combination of the two. In most cases it is partly biological, partly environmental, and partly behavioral. It can manifest itself in withdrawal, fatigue, loss of interest, and difficulty in concentration (among other symptoms) or it can manifest itself in anger and aggression.
Depression often co-occurs with developmental disabilities, physical disabilities and disease, substance abuse, and/or mental health disorders.
Fortunately, in most cases, when diagnosed and treated correctly, depression is easily treatable. There was a time, not so very long ago when it was believed young children could not suffer from depression. That time has past; young children can suffer from depression.
One of the most significant predictors of depressions in an infant is maternal depression. There is appropriate treatment for both the parent and the child. As with most mood or behavioral disorders in children, there is a logical sequence of treatment, with direct treatment for the child being the last option unless the child is in a life threatening situation. When possible, setting events, environmental issues, attachment, nutrition, sleep, hygene, and relationships should be evaluated and ameliorated as needed first, before directly treating or at least as, the child is being directly treated.
Depression in children
When Parents Are Depressed
Parenting a Child with Depression
Depression (major depression) Definition by Mayo Clinic Staff
For additional information please use the Google Parenting and Scholar search engines below.