Yeah, see, the lot of you are confusing. Half these replies aren't even helpful. It's all fine and well that you're thinking "wtf?" but it's hardly a contribution. Thank you to Neel and TurkSlayer for their recommendations; I haven't found any sites pertaining to either Advent Fathers or Third Cousins, but I am on the lookout.

I didn't know that (SPOILER)the Sephiros kids were atheists; thanks FM.

It may just be me, but (SPOILER)Sephiros returning from the dead (he's dead, right?) means he must be an unsent. It makes sense.