So, what causes teen suicide?

According to Berman, about 90 percent of suicidal teens have undiagnosed mental disorders. Depression is the most common, Berman says. But suicide is usually the result of a lot of different factors, including life events that bring some teens down.

After Kayciee's father died, her problems got even worse. At age 14, she discovered she was adopted by her grandparents and that "the family friend I knew as Teresa was really my mom."

Kayciee, like many teens, also felt pressure to do well in school, believing that she had to earn straight A's or "my grandparents would quit loving me."

Eventually, the stress and depression caused Kayciee to plan suicide.

"I've planned suicides in great detail, but I don't think I've really tried."