Corrected entry: The sheet of toilet paper change numbers when Lois tears them off to put on the seat (right before she sees Quagmire peeping on her). She tears off three sheets, but they change to four when she puts them on the seat. (This happens on both sides of the seat).
Corrected entry: When Peter enters Chris' room and accidentally thinks Chris is Lois, he quickly stands up and tries to change the mood by asking Chris questions, one of which is, "Did you do your homework today?" Chris nods his head yes, and Peter comprehends, despite the fact that he is blind.