Pretty strange, this might be more common than you think
... especially in Asia.
I know two women whose fathers had secret multiple families. They were from Asia where I guess it is very macho for a guy who can afford it to have several families and play the big shot.
It happens in America too, but I guess now our families are so broken that they tell everyone about everyone else.
I can't figure why someone would want to do that to a whole family, or why they would.