My son (5) is a very smart kid, he came home from school and said "Daddy, what's Autism?" - Impressed with this inquisition I asked him why, and it turns out he has an autistic friend, Jacob, and they did a class about it or some shit I don't know, but at 5 he can't really grasp the clinical definition, so I sat him down and scrolled slowly down this board. Thread after thread of baby-talk, attention-seeking, shouting and anime. He looked at me and said "I understand now Daddy". Suffice to say, My son is no longer friends with Jacob.