Continuity mistake: In this episode, Doug looks out his bedroom window and sees his parents and Arthur standing on the porch by the front door, but in season one, the episode when Richie sleeps with their neighbor, Carrie and Doug's bedroom window faces the Sacksi bedroom window.
Visible crew/equipment: When Arthur comes out the basement singing Silent Night, he stops and waits a few seconds while trying to remember the next line. Carrie prompts him for this and he thanks her and walks off. As he does, the camera changes angle and a tape marker can be seen on the floor where he stopped to remember the next line in the carol. (00:03:30)A Demon
Other mistake: When arguing with Carrie about having some of the festive cheese platter, Arthur goes for a "spoon to the wheel of brie", but from a previous episode (Ticker Treat S4, E6) we found out that Arthur has banned soft cheeses along with celebrating Halloween. (01:10:20 - 01:10:55)The Minister