https://www.change.org/petitions/set...-to-family-guy
Writer Steve Callaghan told E! Online that Brian's fate was sealed before the season began, when the writers decided killing a character would provide a valuable shakeup.
Callaghan said that however much the characters and viewers loved Brian, the show felt it would be easier to weather his loss than the loss of a two-legged family member.
Brian's departure could potentially change several key dynamics on the show, since he was a sounding board and frequent skeptic about family schemes.
Brian was 11.