A Very Crappy Christmas - S4-E17
Continuity mistake: Cartman is already on stage, but in a next shot he arrives and Stan and Kyle ask him what he's you doing there. (00:16:58)
A Very Crappy Christmas - S4-E17
Continuity mistake: When Kyle tells Mr. Hankey and his family about the $300 he got for the animated Christmas card, the olive stick in the wife's martini glass is facing to the right. When she says to Mr. Hankey "That's not the only thing we've got to get working again if you know what I mean", the olive stick in the martini glass is now facing to the left. The olive stick then returns to facing to the right for the remainder of the scene. (00:07:50)
Answer: He appears in at least 5 other episodes, but usually just as a background character. He can be seen at Cartman's party in "Immaginationland". He was also one of the kids trying out to replace Butters in the "Professor Chaos" episode.
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