To pass his initiation into "The Loyal Order of Alley Cats", Sylvester must put a bell around the neck of Hippety Hopper, the baby kangaroo constantly mistaken for a giant mouse.To pass his initiation into "The Loyal Order of Alley Cats", Sylvester must put a bell around the neck of Hippety Hopper, the baby kangaroo constantly mistaken for a giant mouse.To pass his initiation into "The Loyal Order of Alley Cats", Sylvester must put a bell around the neck of Hippety Hopper, the baby kangaroo constantly mistaken for a giant mouse.