American actor and television director Charles Siebert, best known among fans for playing Dr. Stanley Riverside II on the hit medical drama television series Trapper John, M.D., the spin-off of M*A*S*H from 1979 to 1986, has died. He was 84. The news was confirmed by his daughter Gillian Bozanic, who told The Hollywood Reporter that he passed away due to COVID-related pneumonia on May 1 at the University of California San Francisco Medical Center. Having appeared in all 151 episodes of Trapper John, M.D., Siebert also featured in films in the 1970s among which included And Justice for All, Blue Sunshine, Coma, and The Other Side of Midnight to name a notable few, and also in All Night Long, Eight Men Out and White Water Summer in the 1980s. 

A student at the Marquette University and the London Academy of Music and Dramatic Art, Siebert was an expert stage-trained actor and later became a founding member of the American Conservatory Theater in San Francisco in 1965. In his tribute to Siebert, Craig A. Miller, former artistic director of the 6th Street Playhouse in Santa Rosa penned emotional words and wrote, "Charlie was never one to over-compliment, or gush, or flatter." He added, "He was serious about his craft; he worked hard, and he expected everyone around him to do the same. He lifted us all to a new level of theatricality and magic. As an actor, he didn’t want the praise — he wanted the damn notes." 

Siebert also made a name for himself on Broadway with his appearances in the early 1960s and was first seen on the stage in Galileo in 1967, which he followed up with Jimmy Shine in 1968, while also later bagging a starring role in The Gingerbread Lady in 1970. After landing roles in popular daytime soap operas, including shows like Another World, As the World Turns, and Search for Tomorrow, Siebert moved to Los Angeles and was cast in the pilot for NBC's Good Morning, Miss Bliss in 1987. He went on to appear in guest and recurring roles on shows like All in the Family, including its spin-off Maude, and also on One Day at a Time, Kojak, Murder, She Wrote, Police Woman, The Rockford Files, and The Incredible Hulk