Virginia Madsen is mourning the sudden death of her older brother and fellow actor Michael Madsen, who was found dead July 3 at age 67.

“My brother Michael has left the stage,” Virginia wrote in a statement shared with Variety. “He was thunder and velvet. Mischief wrapped in tenderness. A poet disguised as an outlaw. A father, a son, a brother — etched in contradiction, tempered by love that left its mark.”

“We’re not mourning a public figure,” the Sideways Oscar nominee, 63, said. “We’re not mourning a myth — but flesh and blood and ferocious heart. Who stormed through life loud, brilliant and half on fire. Who leaves us echoes — gruff, brilliant, unrepeatable — half legend, half lullaby.”

Virginia concluded, “I’ll miss our inside jokes, the sudden laughter, the sound of him. I’ll miss the boy he was before the legend; I miss my big brother. Thank you to everyone reaching out with love and memory. In time, we’ll share how we plan to celebrate his life — but for now, we stay close, and let the silence say what words can’t.”

Per NBC4 Los Angeles citing a local sheriff’s department, Michael’s death appeared to be from natural causes, with no foul play suspected. Los Angeles County deputies responded to a 911 call at the Reservoir Dog actor’s Malibu home, according to the outlet. “What we understand is Michael had a cardiac arrest and was found unresponsive in his Malibu home earlier this morning,” Madsen’s manager Ron Smith told PEOPLE.

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Virginia and Michael, who also share sister Cheryl, got their start acting on stages in Chicago, where they were born and raised. The two siblings, who supported each other at each other’s screen project premieres over the years, appeared together in director Michael Mongillo’s 2007 mockumentary Being Michael Madsen, playing fictionalized versions of themselves.

“In the last two years Michael Madsen has been doing some incredible work with independent film, including upcoming feature films Resurrection Road, Concessions and Cookbook for Southern Housewives, and was really looking forward to this next chapter in his life,” the actor’s managers Smith and Susan Ferris, plus publicist Liz Rodriguez, said in a statement. “Michael was also preparing to release a new book called Tears For My Father: Outlaw Thoughts and Poems, currently being edited.”

Michael was previously married to Georganne LaPiere, Jeannine Bisignano and DeAnna Madsen. He shared sons Calvin, Luke and Hudson with DeAnna and sons Christian and Max with Bisignano.