Fox is under pressure to remove a line from its upcoming crossover episode of The Simpsons and Family Guy in which Stewie tells Moe Sizlack, "Your sister's being raped". The episode is due to air on Sunday (September 28, 2014).

The Simpsons Family Guy crossoverThe Simpsons/Family Guy crossover episode airs on Sunday

The much awaited episode sees Bart Simpson and his family hanging out with Stewie and the Family Guy crew. The controversial line appears in a segment in which Bart is teaching Stewie the art of the prank phone call. Bart dials the number of Moe's Tavern and asks if there is anything with the last name Keybum, first name Lee. 

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Stewie thinks the joke is funny and decides to try out his own prank call. "Hello, Moe?" he says. "Your sister's being raped."

Tim Winter, president of the advocacy group Parents Television Council, said he's a big fan of The Simpson but was shocked by the joke.

"I was blown out of my shoes when I saw the scene with the rape joke in it," Winter said. "It really troubled me."

Family GuyStewie's character tells the rape joke

However, Katherine Hull Fliflet, spokeswoman for the Washington-based Rape, Abuse and Incest National Network, said she did not have a problem with the line.

"I think the show is making it clear that rape is not funny by how they are positioning the joke," Fliflet said. "It's my hope that would be the viewers' take-away."

Family Guy creator Seth MacFarlane actually discussed the line during an interview with Entertainment Weekly, predicting that he would get attacked by the media though adding, "But in's pretty funny."

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