I've had ADHD for my entire life. I was also a very anxious and "sensitive" child. I began having intense OCD symptoms at age 11, and had my first psychotic depression at 12. I'm not sure when my mania started. My first clearcut episode occurred at 14, but I had brief periods of elevated mood where I believed I could do anything throughout childhood. I think hypomanic optimism might be normal for children, though...I didn't have suicidal thoughts until I was 15, and they didn't bleed into plans until I was 20.