It happened at the father's home. He has every right to be there, and does not have to explain why, or what he was doing at the time.
I think you misread the comment.
I didn’t ask that in the sense of what business he had being there as much as what he was actually doing in response to it.
Like was he *just standing around* as was observed in post 2?
Trying to stop her? Protect his daughters? Help his daughters? Or was he hurt?