Tell your Dad to Man up and get it sorted seems to be the general consensus.
If there is something in this that we don't know about, like, oh I don't know, he hasn't paid a bill or something then they will sue your arse to kingdom come for defamation.
One piece of advice. I'd make sure your Spazzbook privacy settings are whacked up to maximum as I presume you created this group and therefore have your details there. You may well attract Facebook stalkers. Not me though, I couldn't give a f***ing donkey's scrotum.