Trivia

Attending John's funeral were fellow Irish actors James Cagney, Pat O'Brien and George Brent.

John had eight other brothers and sisters. In addition to silent screen star Robert Harron, they included Charles, Theresa (Tessie), Madeline, Agnes (who became a nun), Mary, Edna, and a daughter who died in childhood. A few of John's other brothers and sisters also appeared in Bobby's films as extras. Of all nine children, John was the only one to marry to continue a new generation. He and wife Betty had one child, Colleene (Harron) Kiley, who ended up having nine children of her own.

Met actress Betty Westmore during the filming of The Man in Hobbles (1928). They married in 1929. Betty abandoned her career for marriage and family. They had one child, Colleene, who was born on August 13, 1930.

Brother of actor Robert Harron.