I hate those cutesy twin names, and how many times are people going to get confused and think the more Caucasian looking girl should be
Ivory, and the darker girl
Ebony. I don't understand why parents have to treat twins like a set rather than two individual people who happened to be born at the same time.
The genetics of this is interesting. The father would have a blonde haired Caucasian relative, for there to be a recessive blonde gene in his DNA. It's possible, but really uncommon.