Rio Hackford, The Mandalorian Actor and Helen Mirren's Stepson, Dead at 51

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Rio Hackford, an actor known for roles in The Mandalorian, Treme, and American Crime Story, has died. He was 51.

The actor, who is the son of director Taylor Hackford and stepson of Helen Mirren, died Thursday in Huntington Beach, California, after an illness, his brother Alex Hackford told Variety.

Mirren, 76, shared a throwback photo in remembrance of her late stepson Saturday on Instagram. "El Rio," she wrote in the caption.

Rio's friend and screenwriter D.V. DeVincentis penned a heartfelt tribute, sharing a black-and-white photo of the late actor. "Rio was more attuned to experience than anyone I've ever known," he wrote in part.

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"He would stop what was happening to point it out, compel you to pay attention," DeVincentis recalled. "He would order you a must-have experience from a beloved menu and hold your eye as you paid attention to what was happening in your mouth. 'Right, Guy? I mean… right?' He would put an experience for you on the stereo, then start it over and play it again for you because we were talking over it the first time and 'Pal, you really have to listen to it.' "

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Others who knew Rio paid tribute in the comments sections of his and Mirren's posts. "This is a massive loss," Lake Bell wrote. "So sorry for your loss. May his memory always be a blessing," Cary Elwes commented.

"I was so sad to hear about Rio passing," wrote Robin Tunney. "I remember him exiting his old yellow cab in late '80s Chicago! The car was enormous but Rio could not be dwarfed by his impractical ride. He was too nice to be that handsome. Too cool to be that relatable. My Gosh that man was special. RIP Rio."

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Rio made his first onscreen appearance in 1990 with Pretty Woman, and he's appeared over the years in such films and TV shows as Swingers, Raising Helen, Deja Vu, Fred Claus, Jonah Hex, and True Detective. His most recent credit was in Hulu's Pam & Tommy.

He also owned several bars, including Monty in Los Angeles, Homestead in San Francisco, and New Orleans clubs Pal's Lounge and One-Eyed Jacks.