Birth of black skin and white skin twin

The probability is really one millionth. I do not know if there are more or less, but that there are such rare examples. Details are as follows.
Black and white twins | the Daily Mail

It was a woman named Kylie Hodgson who gave birth. I heard he was a Caesarean section. The one who was born earlier is Remee, blond hair. And after a few minutes I was born with black hair Kian.

Both mothers and fathers were mixed, and it seemed that the mother was white and the father was black as the father was black. It is a good feeling though it occurs genetically with a tremendously low probability.