Watson was best known for his role as "Pee Wee" in the 1938 Metro-Goldwyn-Mayer film Boys Town and its sequel Men of Boys Town (1941), both starring Spencer Tracy and Mickey Rooney. Tracy and Watson became good friends during the making of the first film, and Watson was reportedly Tracy's last visitor before his death in 1967. In 1939, Watson delivered a fine, tear-jerking performance as Pud, Lionel Barrymore's grandson, in the MGM film, On Borrowed Time. Watson later made guest appearances in many television programs, including The Twilight Zone, Lou Grant, The Beverly Hillbillies, Green Acres, and The Fugitive.
