Geoffrey Deuel, best known for portraying famed outlaw Billy the Kid in the 1970 John Wayne vehicle Chisum, died Dec. 22 at age 81, per an official obituary.

The news was additionally confirmed to The Hollywood Reporter by wife Jacqueline Deuel. The performer, younger brother to Peter Duel (who became known for portraying Hannibal Heyes/Joshua Smith on the popular ABC Western Alias Smith and Jones prior to his suicide), died in hospice care in Florida following a battle with chronic obstructive pulmonary disease.

“He and Peter were very close,” Jacqueline Deuel told THR. “They really loved each other and took care of each other.”

Deuel, who was born Jan. 17, 1943, mostly appeared on television in a variety of series stretching from the late ’60s to mid-’70s. Among those credits are The Monkees, The Invaders, The F.B.I., The Manhunter, Medical Center, Barnaby Jones, Mannix, Adam-12, The Mod Squad, Mission: Impossible, The Streets of San Francisco,...