DNA & family trees in TS4

Hm, I'm currently working on the Capp family.

We don't know anything about Tybalt Capp's wife, do we? She is not listed in the family tree shown in misc videos. But, Tybalt is read haired, and his 3 children Beatrice, Celeste and Virgilio all have different hair colors (brown, black, blond). Based on only one hair gene from each parent, and the fact that none of the kids have red hair, technically Tybalt must have had the children with 3 different females? All dead? Some of the childreen might of course have dyed their hair, but 2 of them? Could it be that Virgilio originally had black hair (ref his beard being black), and  could Beatrice be originally redhaird, but dying it brown? If so, Tybalt's late(?) wife had black hair, and he might have been married just once.

I'll need to see the in game family tree regarding each child's mother to complete my task. Any imput appreciated :)