Merrie Melodies - Pop 'im Pop! (1950)

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A circus comes to town featuring Gracie the Fighting Kangaroo and her youngster, Hippety Hopper. Hippety slips out of the circus tent and hops into a yard where Sylvester Cat is bragging to his son, Junior, about how good a mouser he used to be. To prove he still has his mettle, Sylvester must fight against the playful Hippety, whom they, as usual, mistake for a giant mouse.