[s4e22] | Sibling Rivalry

: The bingeing eventually catches up with Lois, leading to a heart attack. She is rushed to the hospital for emergency liposuction, which returns her to her original size and ends their "weight-gain" phase. The Subplot: Stewie and Bertram

: After undergoing a vasectomy, Peter loses his sex drive, leaving Lois feeling neglected. To cope with her frustration, she begins overeating. [S4E22] Sibling Rivalry

: Stewie encounters his half-brother, Bertram (born from a sperm bank donation Peter made years earlier), at the playground. The two share the same genius-level intellect and megalomaniacal ambitions. : The bingeing eventually catches up with Lois,

: A literal war for "The Hill" at the playground ensues, featuring high-tech weaponry and tactical maneuvers typical of Stewie's sci-fi style. To cope with her frustration, she begins overeating

: The episode includes a shot-for-shot parody of the film Better Off Dead during a drag race scene.

: One famous gag features the letter "Y" being mocked by other vowels for only being a "semi-vowel". Family Guy S4E22: "Sibling Rivalry" Recap - TV Tropes

: Peter finds he is actually attracted to Lois’s new, much larger physique. The two rediscover their spark through what Peter calls "fat sex," and he actively encourages her to continue gaining weight.