Continuity mistake: In season 3, Episode 9, "Holy Matrimony": When Kitty and Robert get married, you see Kitty putting the ring on his finger whilst speaking the vows. Then in the next segment once they have been pronounced man and wife, Robert goes to kiss Kitty and puts his left hand up to her face he has no wedding ring on.
Matriarchy - S1-E23
Continuity mistake: When Justin gets on the escalator after saying goodbye he is standing next to a woman with a black blazer, then the shot changes to Kitty and Nora and when it changes back he is standing next to a woman in a blue shirt.