Are You There God, It's Me Jesus - S3-E16
Factual error: In the episode where Cartman thinks he has had his period, a news report says it was merely a viral infection, simple antibiotics will cure it. Antibiotics are only used on bacteria and have no effect on viruses.
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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