Actor Charles Siebert passed away at the age of 84 on May 1, 2022. He primarily gained recognition for his performance as Dr. Stanley Riverside II on the CBS medical drama series Trapper John, M.D.The 6th Street Playhouse confirmed the news in Santa Rosa, California, where Siebert appeared frequently. Further details on his funeral are yet to be revealed.Mike Barnes@MikeBarnes4#RIP Charles Siebert; after appearing six times on Broadway and as a charter member of San Francisco's American Conservatory Theater, he appeared on every episode of 'Trapper John, M.D.' as Dr. Stanley Riverside II. He died of COVID-related pneumonia. bit.ly/3m1Z0vO4418#RIP Charles Siebert; after appearing six times on Broadway and as a charter member of San Francisco's American Conservatory Theater, he appeared on every episode of 'Trapper John, M.D.' as Dr. Stanley Riverside II. He died of COVID-related pneumonia. bit.ly/3m1Z0vOMatthew Rettenmund@mattrettRIP to familiar TV face Charles Siebert, who died earlier this month of COVID pneumonia at 84. extratv.com/2022/05/31/tra…144RIP to familiar TV face Charles Siebert, who died earlier this month of COVID pneumonia at 84. extratv.com/2022/05/31/tra…Charles Siebert's cause of death and career exploredCharles Siebert died on May 1 from Covid-related pneumonia at the University of California San Francisco Medical Center. There is very little information on when he was hospitalized, and the time he was diagnosed with the disease.Born on March 9, 1938, he first became famous as Dr. Stanley Riverside II on Trapper John, M.D. from 1979 to 1986. Pernell Roberts played the lead role, and the series ran for seven seasons. He later continued working as an actor but also directed episodes for television shows like Xena: Warrior Princess and Hercules: The Legendary Journeys.Charles Siebert with Connie Stevens (Image via ABC Photo Archives/Disney General Entertainment Content/Getty Images)Charles studied acting at Marquette University and the London Academy of Music and Dramatic Art. He first appeared in regional theatre productions across the United States during the 1960s with companies like Shakespeare in the Park in New York City, the McCarter Theatre in Princeton, Chicago's Goodman Theatre, Baltimore's Center Stage, and others.He was a charter member of the American Conservatory Theater and made his Broadway debut in 1967 in Bertolt Brecht's Life of Galileo. He then appeared as Michael Leon in John Sebastian and Murray Schisgal's 1968 musical Jimmy Shine.His other Broadway appearances include The Gingerbread Lady, The Changing Room, Cat on a Hot Tin Roof, Sticks and Bones, and others. He began appearing on New York television during the 1960s and 1970s like Another World, Search for Tomorrow, One Life to Live, etc.Siebert moved to Los Angeles in 1976 and appeared in the 1978 horror film Blue Sunshine. Although the film received mixed reviews, it became a cult classic and was later shown at many film festivals. He began making guest appearances on TV shows like One Day at a Time, The Blue Knight, Mancuso, and others.Charles appeared on the comedy program Husbands, Wives and Lovers and then on the pilot of Good Morning, Miss Bliss. The latter was picked up by the Disney Channel and made many casting changes, including dropping Siebert's role. He appeared in many films from the mid to late 1970s, including ...And Justice for All, Coma, All Night Long, and White Water Summer.Siebert played a supporting role as the mayor of Los Angeles, Frank Baldwin, in the 1990 made-for-television disaster film, The Great Los Angeles Earthquake. The film aired on NBC from November 11 to 12 and focused on seismologist Clare Winslow, played by Joanna Kerns, who tries to warn city leaders that a powerful earthquake may strike southern California.He appeared regularly on game shows during the 80s, including $25,000 Pyramid, $100,000 Pyramid, Match Game, Super Password, etc.Fans pay tribute on TwitterCharles Siebert became a famous name in the entertainment industry due to his flawless performances on film and television. Twitter was flooded with tributes when people heard about his death:LightsCameraJackson@LCJReviewsCharles Siebert. Didn't watch him on "Trapper John, M.D.", but over the past three years I've seen him on a bunch of episodes of the "Match Game / Hollywood Squares Hour" and "Super Password" on @BUZZRtv *promoting* "Trapper John M.D.". Also a frequent "Pyramid" player. #RIP11Charles Siebert. Didn't watch him on "Trapper John, M.D.", but over the past three years I've seen him on a bunch of episodes of the "Match Game / Hollywood Squares Hour" and "Super Password" on @BUZZRtv *promoting* "Trapper John M.D.". Also a frequent "Pyramid" player. #RIP https://t.co/rrWs2Tt2GoPaul Millard@hobodreamer#RIP: Charles Siebert Dead At 84, The ‘Trapper John, M.D.’ “Other Side of Midnight,” “Blue Sunshine,” “Coma” & “And Justice for All.” Actor died on May 1 at the Uni of Cal San Francisco Medical Center from COVID-Related Pneumonia.▼tinyurl.com/bdhwjdmu.#CelebrityDeath21#RIP: Charles Siebert Dead At 84, The ‘Trapper John, M.D.’ “Other Side of Midnight,” “Blue Sunshine,” “Coma” & “And Justice for All.” Actor died on May 1 at the Uni of Cal San Francisco Medical Center from COVID-Related Pneumonia.▼tinyurl.com/bdhwjdmu.#CelebrityDeath https://t.co/BNa509YdL1Bruce Phillips@bephillip33RIP. Charles Siebert, Star of ‘Trapper John, M.D.,’ Dies at 84 yahoo.com/entertainment/… via @YahooRIP. Charles Siebert, Star of ‘Trapper John, M.D.,’ Dies at 84 yahoo.com/entertainment/… via @Yahoorich cerasale@chewy7rip actor/director Charles Siebert at the age of 84rip actor/director Charles Siebert at the age of 84Harold Brian Krieg@HaroldBKrieg@MikeBarnes4 @THR RIP Charles Siebert.@MikeBarnes4 @THR RIP Charles Siebert.Amanda Reyes@madefortvmayhemMy beautiful Dr. Riverside. Absolutely one of the most delightful, wonderful faces I'd see on my TV. I'm so sad. deadline.com/2022/05/charle…262My beautiful Dr. Riverside. 💔💔💔Absolutely one of the most delightful, wonderful faces I'd see on my TV. I'm so sad. deadline.com/2022/05/charle…Alisha Doutt@AlishaDoutt@TheRealGregoryH Hi Gregory I'm so sorry about your friend & former co star Charles Siebert He was a wonderful actor & director & a kind hearted man He was great on many game shows too Condolences to you your former colleagues, the Siebert family, Charles' friends & fans@TheRealGregoryH Hi Gregory I'm so sorry about your friend & former co star Charles Siebert He was a wonderful actor & director & a kind hearted man He was great on many game shows too Condolences to you your former colleagues, the Siebert family, Charles' friends & fansZig Fracassi@ZigFracassiR.I.P. Trapper John, M.D. actor Charles Siebert msn.com/en-us/tv/news/…21R.I.P. Trapper John, M.D. actor Charles Siebert msn.com/en-us/tv/news/…Charles is survived by his wife Kristine and children Gillian and Christopher.