Spencer Milligan, Actor Known for “Land of the Lost”, Dies at 86: 'Our Loss Is Great'

The actor's former onscreen kids Wesley Eure and Kathy Coleman said they were "heartbroken" at the loss

Ron Tom/NBCU Photo Bank/NBCUniversal via Getty Spencer Milligan as Park Ranger Rick Marshall on 'Land of the Lost'

Spencer Milligan, best known for his leading role in the 1970s hit series Land of the Lost, has died. He was 86.

Milligan died on April 18, according to an obituary posted on a Wisconsin funeral home's website. No cause of death was listed.

Born in 1937 in Oak Park, Illinois, Milligan served in the U.S. Army and was honorably discharged in 1966. He was a performer and lover of the arts from a young age, training at several prestigious programs, including Chicago's Goodman Theatre, the Joan Darling Actors Workshop in L.A., and New York's Lee Strasberg Senior Workshop.

He lived in Malibu, Calif. between the 1970s and 1990s, and guest starred in many of the era's best-known shows, including The Bionic Woman, Gunsmoke, Alice, Mike Hammer and McCloud. His roles in the shows varied "from gunslinger to hitman, grief-stricken father, drug-pushing medical lab supervisor, and broad comedy," the obituary noted.

Per the online obituary, among the actor's "favorite" roles were leading ABC's Call of the Wild, "starring as a troubled Jet’s Quarterback in The Keegans, and guest starring as a punch-drunk boxer in Good Time Harry."

Ron Tom/NBCU Photo Bank/NBCUniversal via Getty Wesley Eure as Will Marshall, Spencer Milligan as Park Ranger Rick Marshall, Kathy Coleman as Holly Marshall on 'Land of the Lost'

Mulligan's role as park ranger and father Rick Marshall in Land of the Lost is what he was best known for.

Wesley Eure — who played one of his onscreen children, alongside Kathy Coleman — paid tribute to his former onscreen dad on Instagram on June 25, writing that he and his former costars are "heartbroken" at the loss.

"For many of us, and Spencer's many fans, he was the perfect dad. We loved his kindness, talent and huge sense of humor," Eure wrote. "We are just processing this news and will post more in the coming days. Our hearts go out to his lovely wife and Spencer's many friends and family."

He noted Mulligan "was a very private man who lived a wonderful life away from the world of Hollywood."

"Our loss is great.... Rest in peace my dear, dear Papa," he concluded the tribute.

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NBCU Photo Bank/NBCUniversal via Getty Spencer Milligan as Park Ranger Rick Marshall on 'Land of the Lost'

Despite only playing the character on Land of the Lost for two seasons, from 1974 to 1975, Milligan described the series as "part of television history" in a 2018 interview with the Green Bay Press Gazette.

"It's part of my life. It's not my full life. I did what I wanted to do and that was it. For the time, I though it was very good. We had some fun with it," he said of the series, which he attended a convention for in Milwaukee in 2018, much to his surprise.

"It was remarkable. I had never done anything like this before," he said of the fans' response to his presence at the convention.

Mulligan left Hollywood shortly after he ended his run on Land of the Lost, relocating to Sturgeon Bay, Wisconsin, where he'd spent his summers.

Over the last 20 years, he "dedicated his time and energy to furthering his love for theatre in his community," per the obituary, teaching classes and directing plays. "His commitment to his community and his love for theatre were evident in these efforts, and his impact will be felt for years to come."

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The actor is survived by his wife, Kerry Milligan, and godchildren Andee Solis, Hilary Williams and Spencer Williams.

Read the original article on People.