When Lois rescues Stewie's teddy bear, Rupert, Stewie becomes obsessed with his mother.
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Family Guy Season 5 Episode 1 Quotes

Stewie: (Comes into the bedroom) Lois! Lois! Lois! Lois! Lois! Lois! Mom! Mom! Mom! Mommy! Mommy! Mommy! Mama! Mama! Mama! Ma! Ma! Ma! Ma! Mum! Mum! Mum! Mum! Mummy! Mummy! Mumma! Mumma! Mumma!
Lois: What!?
Stewie: Hi! (Giggling and running out of the room)

Brian: (teasing) Stewie loves Lois.
Stewie: Brian loves Olympia Dukakis.
Brian: Oh, yeah I do.