I think the father may be her actually father but he probably married the mother to raise ...

I think the father may be her actually father but he probably married the mother to raise his status therefore he doesn't truly live his daughter and be see Vienna as a younger version of himself striving for more, so he feels more affectionate towards her. I think they may be cousins throught the father side since Vienna looks nothing like him but has brown hair like her father so I think that's why he may also like her more