I don't have a brother so I've never observed this in action. I sincerely wonder: how early do boys start understanding that they were born into the high caste of humans while their mothers belong to the low one? How do they reconcile this with being totally dependent on an 'inferior being' and her being the most important person in their world for a long time?
I know that this starts happening really young in the really partriarchal environments. But what about the secular 1st World one?