Kelley Mack, The Walking Dead Actress, Dies at 33 After Glioma Battle

CINCINNATI, OH—Kelley Mack, beloved for her role as Addy on The Walking Dead, passed away at 33 on August 2, 2025, after a seven-month fight with glioma, a rare brain cancer. Her family shared the news on Instagram, noting she died peacefully with her mother, Kristen, and aunt, Karen, by her side.

“It’s with deep sadness we announce Kelley’s passing,” her sister Kathryn wrote. “Her bright spirit lives on as butterflies for loved ones.” Kelley’s vibrant energy touched many. For more on her career, visit IMDb.

Mack shared her diagnosis in January, detailing persistent back pain and leg issues from a spinal tumor. “I lost leg function after biopsy surgery,” she posted on Instagram. “I use a walker and wheelchair now, but I’m determined this is a short chapter.” Her optimism shone through. In March, she celebrated walking stairs with her boyfriend, Logan.

Known for playing Addy in The Walking Dead’s ninth season (2018-2019), Mack also appeared as Penelope Jacobs in Chicago Med and in 9-1-1. Her co-stars paid tribute. Director Michael Satrazemis called her “a bright light,” while Alanna Masterson praised her incredible spirit. Gustavo Gomez and Michael Lopez echoed her warmth. See more tributes at Hollywood Reporter.

A remembrance is set for August 16 in Ohio, with a Los Angeles celebration planned. Mack’s legacy endures through her storytelling passion and roles in films like Universal (2025).