I'd let my wife get fucked too. Just to make sure she's a bitch. Any chick's just waiting for that. That blonde doesn't mind being fucked all over. That dog with the rubber band ain't her husband, that's for sure. And the hubby, as the owner of the chick, fucks her without too much precaution.
Lady looks like a long time unsatisfied walks, if so easily with her son and daughter was able to go to such sexual intercourse, while she herself has inclined them to it. The son was not confused, noticing through the keyhole what the mother and sister were doing, decided not to lose the opportunity and joined in. Especially since he had previously looked at family photos and became aroused. It was a sin not to take advantage of the depravity of his family.