 Alex Borstein was cast as Lois Griffin , Tricia Takanawa , Loretta Brown , and Lois ' mother Barbara Pewterschmidt . Borstein was asked to provide a voice for the original pilot while she was working on MADtv . She had not met MacFarlane or seen any of his artwork and said it was " really sight unseen " . At the time , Borstein performed in a stage show in Los Angeles , in which she played a redheaded mother whose voice she had based on one of her cousins . The voice was originally slower , but when MacFarlane heard it , he replied " Make it a little less [ ... ] annoying ... and speed it up , or every episode will last four hours " . Seth Green was chosen to play Chris Griffin and Neil Goldman . Green stated that he did an impression of the " Buffalo Bill " character from the thriller film The Silence of the Lambs during his audition . His main inspiration for Chris ' voice came from envisioning how " Buffalo Bill " would sound if he were speaking through a public address system at a McDonald 's . Lacey Chabert was cast as Meg Griffin . Chabert voiced Meg Griffin for the first production season ( 15 episodes ) , but due to a contractual agreement was never credited . Chabert left the series because of time conflicts with schoolwork and her role on Party of Five , and was replaced by Mila Kunis . 
