Many require medication. Reassure the children of depressed parents that the illness is not their fault. Otherwise, children may blame themselves for the parent's condition, feel guilty, and become more vulnerable to depression themselves. Also reassure the parents of depressed children in the same way. The depressed person has to get professional treatment.
Many experts believe that social support also helps treat depression.
Keep reaching out to your depressed loved one, just to reinforce the fact that you care. Send affectionate notes. Invite the person to movies, concerts, ball games, parties, and other events. Chances are that the depressed person won't respond to you, or that if you get a response, it won't be that of a normal individual. But depressed people notice outreach efforts and appreciate them, even though their illness renders them incapable of acknowledging your love and devotion.