Redheaded Stepchild

Someone used the term Red Headed Stepchild in a meeting today. One of his adopted kids is red headed. Cute as a button too. He didn’t realize it is a derogatory term. There are all kinds of definitions on the internet. The way I heard it is in the next paragraph.

When the Nomen invaded England, there was a lot of rape involved. A disproportionate number of the offspring were blond and redhead. Every time the parents looked at that child it reminded them of the mother getting raped and thus the prejudice against redheads was born.

No idea if this is accurate. Makes sense in a sick sort of way. I don’t remember where I heard it.