destroyed my family. >> reporter: by the time rachel was in middle school, don's string of affairs led to a home-shattering divorce. >> i think that the -- the obliteration of the nuclear family had a profound effect on rachel. >> reporter: now, he feared, the apple hadn't fallen far from the tree. his daughter rachel was in the middle of an affair herself and it was putting her marriage at risk. >> you know todd had been calling me, you know, "what am i gonna do? you know, how am i gonna save my marriage?" and i said, "todd, have you just told him straight up to stay away from your wife until this thing is worked out?" he said no. and i said, "well, have you thought about that?" he says, "well, not til right now. sounds like a good idea. will you come with me?" "yeah, i'll go with 'ya." and -- so we drove over there. >> reporter: james' daughter katelynn, 16 then, sounded the alarm as rachel's worried father and betrayed husband pulled up at the entrance to james's