Donald David Dixon Ronald O?Connor was an American dancer, singer, and actor who came to fame in a series of movies in which he co-starred alternately with Gloria Jean, Peggy Ryan, and Francis the Talking Mule. Perhaps his most famous performance was as Gene Kelly's friend and colleague in Singin' in the Rain. Though he considered Danville, Illinois to be his home town, O?Connor was born in St. Elizabeth Hospital in Chicago, Illinois. His parents were Irish American vaudeville entertainers. When O'Connor was only a few years old, he and his sister Arlene were in a car crash outside a theater in Hartford, Connecticut; O'Connor survived, but his sister was killed. Several weeks later, his father died of a heart attack while dancing on stage in Brockton, Massachusetts. O'Connor at the time was being held in the arms of the theater manager Mr. Maurice Sims.
O'Connor began performing in movies in 1937. He appeared opposite Bing Crosby in Sing, You Sinners, and at age 12 showed excellent comedic timing. Paramount Pictures used him in both A and B films, including Tom Sawyer, Detective and Beau Geste. In 1940, when he had outgrown child roles, he returned to vaudeville.
In 1942 O'Connor joined Universal Pictures. He played roles in four of the Gloria Jean musicals, and achieved stardom with Mister Big .