I have yet to read here that any of this behavior could be environmental. My Grandson was diagnosed ADHD in kindergarten. Dad was verbally, emotionally and times physically abusive to his mother. Dad was in and out of prison. Dad’s discipline was inconsistent and often times very childish like. My Grandson is 8, and he is academically successful, in the school’s gifted program and very creative. Mom left Dad and is working on a more positive and non violent home atmosphere. Grandson realizes his father’s behavior and does not want to be around him. He still has outbursts and some anger. Now therapy needs to be in order here. I feel as I have seen home life with my daughter’s family that my Grandson’s anger and defiance may have been learned from his father. Anyone else want to chime in here?