He's not dead, so no one killed him.
If you're referring to the previous timeline seen in the episode Life of Brian, the answer is still no one killed him. Meaning the person that was driving the car was not relevant to the story so they were not shown, it was just a speeding car.
He was run over and killed by a car in Life of Brian & Stewie altered the time line and saved him in Christmas Guy.
Brian Griffin
Peter Griffin, Stewie Griffin, Brian Griffin and Glenn Quagmire as well as Tom Tucker , Stan and Roger ,
That information is unknown.
Brian died November 24th 2013, in the 6th episode of Season 12 | Life of Brian.---In the 8th episode Christmas Guy that aired on December 15th 2013, Stewie altered the time line and Brian was never hit & killed by the car, thus returning to the show.
No; he only voices Stewie Griffin and Brian Griffin.
Brian Griffin was created in 1999.
Really, Brian Griffin? You want to know who Brian Griffin lives with? Do you think he may live with The Griffins.
Brian C. Griffin was born in 1953.
Brian Griffin's drink of choice is usually a martini.
Brian Griffin's House of Payne was created on 2010-03-28.
brian smetters is oringanaly brian griffin. he is the dog in the house
Brian Griffin
It is Brian Griffin
Lois Griffin is alive, but Stewie killed her in a simulation in the 100th episode
Are you asking if the driver of the car that killed Brian in the alternate time line was a squirrel? No. The driver was unimportant to the storyline & not focused on, but there's no conceivable way it was a squirrel.
Peter Griffin, Stewie Griffin, Brian Griffin and Glenn Quagmire as well as Tom Tucker , Stan and Roger ,
Brian has a liberal political philosophy