Family Guy S14 E06 Peter's Sister

"Don't die laughing. We could get sued."

Peter’s sister, Karen, decides to come for Thanksgiving and bullies Peter the same way Meg treats him. While Meg is at first amused, she later feels badly and decides to help Peter train to defeat his sister in a wrestling match. Meanwhile, to avoid overeating on Thanksgiving, Stewie and Brian decide to go on a cleanse, which Stewie takes one step too far.