Boo

From Pixar Wiki

Performer:	Mary Gibbs
Appeared in:	Monsters, Inc.

Boo is a three-year-old human child who has escaped from her room from which Randall intended to kidnap her. Much of the film's plot follows what happens as Mike Wazowski and Sulley try to get Boo back to safety. When she first appears, Boo is very attached to Sulley, calling him 'Kitty,' but he is not so keen. But as the film progresses, he develops a bond with her. Boo is voiced by Mary Gibbs.

Quotes

"Boo!"
"Kitty!"
"Mike Wazowski!"

—Boo