This was my comment: You're right, most prejudices are passed down, generation to generation. Ignorant to ignorant. Parenting is hard work and many aren't prepared.
When we raised our daughters, I emphasized, avoiding prejudice and presenting diversity. It wasn't easy, we lived in a very nice white-bread neighborhood. On of the things I did as a SAHM, was to enroll my girls in pre-school, not just any pre-school, but the Child Study Center, at Long Beach City College. There were two campuses and two Child Study Centers. I chose the furthest away from our white-bread neighborhood, in order to give our children the broadest exposure to people who were different from us. I'd say my experiment worked. Our daughters' friends are a wonderful mix.
I'm not going to post about what a wonderful parent I was/am, because I know I failed in many ways. But, I will tell you, any time you ask, what wonderful daughters we have.