I concur with the above statements. This is becoming really dark, really fast. I still stand by my view that Max and Vic have brought their kids up in a way that would make them hate each other, and the only way for them to ever stop fighting is to realize there's no point to it, when they're just engaging in a proxy-war between dead parents.
Jack/Jill is no different than Silver from Pokémon, to further Nonesuch's comment. Someone who's an asshole due to poor/neglectful parenting who end up despising (or even envying) the Player for their ability to constantly best them, despite always seemingly being one step ahead.
The adult thing to do is talk it out. And then some incest action, why the fuck (k)not? Maybe even include Dane and Anno, as they seem to share the role of Confidant to the Steeles.