It's hard to believe the continuity that Family Guy creator Seth MacFarlane sometimes invests in the show; four seasons after Peter crashed the Petercopter for example, Lois made a reference to their financial situation, and claimed it was down to the catastrophic flying machine. Likewise, it came out in an interview that Peter had destroyed a children's hospital, and that just because this is a cartoon, it didn't mean people had forgotten. So why exactly has Stewie Griffin turned from a matricidal villain to Brian's camp, child-genius sidekick? In the early days of the show, a Stewie subplot would revolve around plans to kill Lois, as the main action focussed on Peter. Stewie's schemes wouldn't come to anything, and it was often implied that this aside was simply happening in Stewie's imagination; he didn't really interact with anyone else, as he was just a baby. As the show's grown though, Brian and Stewie have been embarking on adventures together, meeting the likes of Vladimir Putin and visiting a plethora of parallel worlds amongst other things. The recurrent gags are are important ever; Stewie has finally killed off Vern and Johnny, bringing more of a close to an aside than his own character development, and Cleveland's bathroom still gets destroyed, even with him gone. The desire to kill Lois hasn't been mentioned for years though, and the references to Stewie's sexuality have gone from mild insinuations to the character enacting full-blown fantasies. Many cite Stewie's "outing" as one of the reasons the show's headed downhill, and some seem to think that maybe Roger from American Dad has influenced Seth MacFarlane's decision to change Stewie. Every character in the series has changed, but he seems to assumed a completely different role within Family Guy; maybe that's all part of his character growing up though.
