I have said for years that we do the same in a non-violent context. What does it do to the psyche of a 4 year old boy who is told "you're the little man", "Daddy is gone for a week, you're the man in the family now." We don't put that pressure on little girls. Can you imagine? Telling a 4 year old girl -- "you're the little woman"? That is yucky for little girls, it is yucky for little boys.