During the 21st Academy Awards (presented on March 24, 1949), Walter and John Huston became the first father/son duo to win an academy award. Walter Huston won the best supporting actor award while his son, John Huston, received an Oscar for directing. They both won for their work in The Treasure of Sierra Madre. The film also received the award for best screenplay.
Kane, Joseph Nathan, Steven Anzovin and Janet Podell. Famous First Facts. 5th ed. New York: The H.W. Wilson Company, 1997, 56.
Photo via The Academy of Motion Picture Arts and Sciences website