Plays the piano.
Son Conor Duffy played "Little J.R." on the final episode of "Dallas" (1978) in 1991.
Son Padraic Duffy played "Mark Harris" on "Dallas" (1978). "Mark Harris' was the name of Patrick's character on "Man from Atlantis" (1977).
Son, Conor Duffy, graduated from the University of Washington, Seattle in June 2001 with a degree in Drama.
Son, Padraic Duffy, graduated from Princeton University in 1996.
Stated on "Politically Incorrect" (1994) that he has been a Buddhist for the past 30 years. [August 1999]
Stated that he was unhappy with the final episode of "Dallas" (1978) because it broke away from the format that defined the show.
Two sons Padraic Duffy (b. 1974) and Conor Duffy (b. 1979).
Wears a medical alert bracelet on his right wrist to draw attention to his potentially fatal penicillin allergy.
While trying to make it as an actor he worked over a year as a grocery delivery man, among other positions.