@Karmichel I don't think they are. Far as I can tell, his dad and her . . . mom, was it? both left their respective spouses to run away together,
after he was already born. Then his dad came back after a while and has been acting like nothing ever happened, but OL's relative never came back at all. So he has a home put back together at some time before he was really paying attention, while OL's remained broken. So his mom is
not someone who ran away--she is as much, or more, a victim than anyone.
So OL has reason to be righteously pissed off at his dad, but as she says, it's not his fault.
We don't know of the runaways having any kids while his dad was gone, but we also don't know there are none--somebody could turn up at some point.