Bigunks, you might be correct and if I am wrong I take that part...

Bigunks, you might be correct and if I am wrong I take that part back but in my experience most of the time the birds of a feather flock together is my experience. Not always but my experience is family members are often coming from a similar moral/ethical level. Rarely are the family members completely unaware and even their mates. Most people's views of the world are based on one's own personal experiences and my experiences have led me to believe the bird of a feather statement is generally true.
One always tries to teach their own kids to behave in a moral and ethical manner but unfortunately for much of the world out there this no longer seems to be the norm from my experiences. Hopefully your experiences have been more positive.