Rooney was the eldest of Mickey Rooney's nine children.

Mickey Rooney Jr., an original Mouseketeer, actor, and musician who was the eldest child of screen legend Mickey Rooney, died Saturday at his home in Glendale, Az. He was 77.

Rooney's longtime companion Chrissie Brown confirmed his death to The Hollywood Reporter and said the cause was unknown.

Paul Petersen, a fellow Mouseketeer, paid tribute to Rooney in a Facebook post over the weekend. "I first met Mickey, the oldest of nine siblings sired by his famous father when he and Timmy were hired by Disney to be Mouseketeers in 1955," he wrote. "Mickey Junior was tall and talented. He could sing, dance and act…and get in trouble. We three were fired for Conduct Unbecoming a Mouse! Mickey Junior was the personification of 'damaged goods.' He gave all he could."

Mickey Rooney Jr.
Mickey Rooney Jr.
| Credit: Bettmann/Getty Images

Born Joseph Yule III in Birmingham, Ala., to his famous father and Betty Jane Baker, a former Miss Birmingham, Rooney landed a job on The Mickey Mouse Club with his brother Tim in 1955, but they only worked on the show for a short time before being fired. Rooney went on to make a name for himself through his music career.

Rooney played guitar, keyboard, bass, drums, and harmonica, and performed in bands with Willie Nelson. He also logged appearances with Nelson in the films Honeysuckle Rose and Songwriter. Rooney recorded several songs, including "The Wandering Wind," "It Certainly Ain't a Nice Thing," and "The Choice is Your"; appeared on the ABC music show Shindig; and scored the soundtrack to and appeared in Hot Rods to Hell. He also had in a role in the NBC movie Beyond the Bermuda Triangle.

Rooney was previously married to Merci Montello and Laura Hollander before meeting Brown nearly two decades ago. Brown told THR that Rooney had overcome drug and alcohol problems he'd struggled with earlier in life. "He was a wonderful man," she said. "The last 18 years with me and my family, he's been an angel."

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