Maxine tells Waldo she's an only child, but in season 8's Le Jour D'Amour, she has a niece named Kelsey.
When Waldo surfaces in the bathtub to answer his phone, you can clearly see he's wearing long shorts.
Carl never considered taking Richie to the dentist to get his loose tooth pulled.
The boom mic is briefly visible when Carl and Harriette are speaking in the living room.