All parents can relate to the many changes their kids go through as they grow up. But sometimes it's hard to tell if a child is just going through a "phase," or showing signs of something more serious. In the last decade, the number of children receiving the diagnosis of bipolar disorder, sometimes, called manic-depressive illness, has grown substantially. But what does the diagnosis really mean for a child? This booklet discusses bipolar disorder in children and teens. Bipolar disorder, also known as manic-depressive illness, is a brain disorder that causes unusual shifts in mood, energy, and activity levels. It can also make it hard to carry out day-to-day tasks, such as going to school or hanging out with friends. Symptoms of bipolar disorder can be severe. They are different from the normal ups and downs that everyone goes through from time to time. Bipolar disorder symptoms can result in damaged relationships, poor school perfor¬mance, and even suicide. But bipolar disorder can be treated, and many people with this illness can lead full and productive lives. Symptoms of bipolar disorder often develop in the late teens or early adult years, but some people have their first symptoms during childhood. At least half of all cases start before age 25. Bipolar disorder tends to run in families. Children with a parent or sibling who has bipolar disorder are up to six times more likely to develop the illness, compared with children who do not have a family history of bipolar disorder. However, most children with a family history of bipolar disorder will not develop the illness. Currently, there is no cure for bipolar disorder. However, treatment with medications, psychotherapy, or both may help people recover from their episodes, and may help to prevent future episodes.