There were a lot of warning signs that I had a mental illness, long before my first diagnosis.
My mother was diagnosed with bipolar disorder when I was a child.
I would have massive mood swings and extremely violent temper tantrums that often resulted in the destroying of objects or attempts to physically injure someone. This resulted in me going to therapy as a young child. To my knowledge, mental illness was never discussed with my parents, and it was never mentioned to me that I can recall.