Looney Tunes Baseball Card 228

Hippety Hopper is a young kangaroo cartoon character in the Warner Bros. Robert McKimson introduced Hippety Hopper in "Hop, Look and Listen" (1948), which created the mold into which future Hippety Hopper cartoons would fall: baby kangaroo Hopper escapes from the zoo, the circus, etc., and is mistaken for a giant mouse by Sylvester the cat. Sylvester tries to capture and eat his "prey", but the innocent and infantile Hippety mistakes Sylvester's predations for a game — a game of rough-housing, to be exact. Sylvester is repeatedly punched, kicked, juggled, spun, and pounced, but each failure only cements his will to have the "mouse" for lunch. The cat's dignity will suffer no less. The character would later return in McKimson's "Pop 'Im Pop!" (1950) in which proud papa Sylvester boasts of his mousing skills to his son, Sylvester Junior. In "Cat's Aweigh," (1953) Sylvester Cat accepts a position as mouse-catcher on a ship. He encounters Hippety Hopper being shipped from Australia. Sylvester mistakes Hippety Hopper once again for a giant mouse, and the baby kangaroo promptly beats the cat to a pulp. Junior is mortified, but the true victim is Sylvester, humiliated by a mere "mouse" in front of his own son.

Sylvester Junior is an animated cartoon character. He is the son of Sylvester in the Looney Tunes cartoons
Physically, Junior is basically a miniature version of his father, having a large head in proportion to a small body. Junior has been noted saying that he is three and a half years old. His first appearance was in the short Pop 'Im Pop!, directed by Robert McKimson. Mel Blanc and Joe Alaskey (after Blanc's death) voiced both father and son.
Junior's personality reflected a degree of respect for his father, though often, when Sylvester did something embarrassing or humiliating, Junior would melodramatically often profess feeling ashamed or embarrassed by his father's behavior (sometimes donning a paper bag over his head).