I’m watching last Sunday’s Family Guy. Brian says, ‘How would you feel if you killed a baby?’ Stewie says, ‘I’ve killed seven.’
Has Stewie actually ever killed anyone?
Matthew Mcconaughey
His babysitter’s boyfriend
The guy in the house that he and Brian were renovating.
BOOM!
ETA:That cult leader, I think.
another ETA:The cell phone guy in the elevator in future San Francisco.
The New Brian.
I believe he killed the Doctor who slapped him @ birth (though he killed him later on not AT birth). Also, he’s murdered plenty of Peter’s Sperm cells that were each piloted by mini-people.
IIRC, he killed that child actress – Olivia? – and her boyfriend when he set their place on fire.
At least he got to listen to the Streaks before he perished.
OAT: I can’t remember; what happened to Stewie’s “brother” that second time they crossed paths, on the playground?
Heck, Stewie even killed himself. In one episode he travelled forward through time and saw the life his pathetic adult self had, travelled back to warn himself and the warned-Stewie blew away time-traveller-Stewie.
He killed Mort Goldman in the time travel episode. And an entire U-boat crew.
They fought, but neither finished off the other. I think their mothers took them away?
Also, do you count the sperm “pilots” as people? Potential people? 
As I recall, there was an episode with a running gag where a couple guys were singing and playing the piano. The third time or so, Stewie shot them to death and announced “OK? We’re not seeing them again. They’re not coming back.”
Vern and Johnny appeared once each in 6 different episodes, dying in their 5th appearance. (Vern appeared as a ghost in the 6th, Johnny was in hell.)
But it was Stewie who killed them.
He and Peter are also responsible for the death of Mr Penisberg (who ran the SuperstoreUSA).
He apparently killed Chris’s wife from the alternate future, but that scene seems to be cut from TV airings, and I haven’t seen the DVD version.
Olivia apparently appeared after the fire, so she survived. The Alan Alda-ish dude she was cheating with, I don’t know, though.
“Now you might be wondering why Johnny’s in hell. Well Johnny liked little boys…”
He blew Denise Crosby away to make a point to the other Next Generation cast members.
Yes, he went back in time to their wedding, blew her away with a rocket launcher (as a condition for Lois helping him get back to his own time), and continued on to warn himself about his pending near-death experience (resulting, of course, in his getting killed by Stewie)
I think it’s clear that Peter’s sperm are sentient beings, and that Lois is only an incubation chamber with no actual genetic relationship to her children. This explains Meg’s lack of hotness and excuses Chris’s (quasi) incestuous longing for her.