Did you get that? Dad goes away to war and mom takes it out on the kids - the likelihood triples! But when mom's away and the kids stay with dad, he's no more likely to abuse them than if she'd stayed.
Of course, it's no surprise at all that the article blows off dad's restraint by explicitly claiming he must be getting more support from elsewhere and poor, victim mom isn't, left bereft and on her own, but this is nothing in the face of the bare fact of the study.
Now I wonder what happens in the aftermath of divorce, eh?