Junior first appeared in the 1950 short Pop 'im Pop!, directed by Robert McKimson and eventually appeared in a total of 11 shorts in the Golden age. His voice was provided by Mel Blanc until his death in 1989, and later by Joe Alaskey.
He is the son of Sylvester the Cat. Physically, Junior is basically a miniature version of his father, having a large head in proportion to a small body. Aside from Goldimouse and the Three Cats, his mother is never seen nor mentioned in the Warner Bros. shorts, and the only apparent trait Junior got from his mother is his ability to speak without his father's characteristic lisp. Junior has been noted saying that he is three and a half years old.
Junior's personality reflected a degree of respect for his father, though often, when Sylvester does 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) or sadly saying, in a breathy voice, "Oh, Father...", "Oh, the shame of it", or "How can I ever face the fellows in Troop 12?"
Often, Sylvester and Junior's shorts would feature Sylvester trying to capture Hippety Hopper, a baby kangaroo, to prove a point to his son. Each attempt at capture, of course, failed miserably, owing to Sylvester's invariably mistaking the kangaroo for a "giant mouse", and as such being taken completely by surprise by the kangaroo's athletic prowess, with Sylvester losing every fight, often in spectacularly humiliating fashion. In one particular ship based short Junior was able to outdo his father by capturing Hippety, playing on Hippety's playful nature. Though Tweet Dreams was the only pairing of Junior and Tweety in the Looney Tunes shorts, it was not a direct one; Junior basically served as a flashback image of Sylvester himself when he was his son's age.
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