Who provides Boo's voice in Monsters, Inc.?

Who provides Boo's voice in Monsters, Inc.? Mary Gibbs provides Boo's voice.

Boo is the three-year-old human girl who accidentally enters the monster world through a closet door. Although she is central to the story, much of her vocal performance consists of giggles, cries, babbling, and playful reactions rather than conventional scripted dialogue. Gibbs was a toddler during production, so Pixar recorded her through games and situations designed to capture spontaneous reactions.

The recording process became famous because Gibbs was energetic and difficult to keep in one place; crew members reportedly followed her around the Pixar offices with a microphone. Sulley calls Boo “Kitty,” because she refers to him as a cat-like creature, while her real name is never spoken in the film. A tie-in book used “Mary” as Boo's real name, which can blur the line between the character and the actress.

Mary Gibbs also contributed archival Boo recordings to related Pixar projects, including Monsters University. Common mix-ups include Jennifer Tilly, who voices Celia Mae, and Bonnie Hunt, who voices Ms. Flint.