“The Walking Dead” Star Kelley Mack Dies at 33 After Rare Cancer Battle
Kelley Mack (born Kelley Lynne Klebenow), best known for her role as Addy in season 9 of The Walking Dead, passed away on August 2, 2025, in her hometown of Cincinnati, Ohio, at just 33 years old, after battling a rare and aggressive cancer.
Her family shared the devastating news in a heartfelt Instagram statement on August 5, saying:
“It is with indelible sadness that we are announcing the passing of our dear Kelley. Such a bright, fervent light has transitioned to the beyond… Kelley passed peacefully… with her loving mother Kristen and steadfast aunt Karen present. Kelley has already come to many of her loved ones in the form of various butterflies. She will be missed by so many to depths that words cannot express.”
Her sister Kathryn added the following tribute:
“She would want you all to know how much she loves you… she was so brave… I’m so f‑‑‑ing proud of her.”
A celebration of her life is planned for August 16 in Ohio, with another event to follow in Los Angeles.
Her Acting Journey & Legacy
Breakout Role: Mack played Addy in five episodes during Season 9 of The Walking Dead (2018).
Other Work: She had guest roles on 9‑1‑1 (2019) and Chicago Med (2022), appeared in films including Broadcast Signal Intrusion and Delicate Arch, voiced Gwen Stacy in Spider‑Man: Into the Spider‑Verse, and appeared in commercials for Dr Pepper, Chick‑fil‑A, and Rakuten.
Education & Background: Born July 10, 1992, in Cincinnati, she graduated from Hinsdale Central High School (2010) and earned a cinematography degree from Chapman University in 2014.
Filmmaking Passion: She co-wrote scripts with her mother and worked behind the camera on original projects like Positive, A Knock at the Door, and On the Black.
Health Battle with Glioma
Diagnosis & Symptoms: In September 2024, Mack was diagnosed with diffuse midline glioma (DMG), a rare cancer of the central nervous system. Early symptoms, including persistent lower back pain, neuropathic itching, and shooting leg pain, prompted emergency imaging and subsequent diagnosis.
Physical Impact: Biopsy surgery affected her spinal cord, causing paralysis in her right leg and reduced use of her left. She documented her rehab efforts, often guided by her boyfriend Logan, sharing public updates on her progress.
Rare, Aggressive Illness: Diffuse midline glioma is particularly insidious, growing along areas essential to basic functions and resisting surgical removal. Its prognosis is especially grim, often affecting young adults.
Tributes & Survivors
Colleagues and friends paid tribute across social media. The Walking Dead director Michael E. Satrazemis remembered her as “a bright light,” while co-star Gustavo Gomez described their meeting as “heartwarming” and shared his grief. Actor Anthony Michael Lopez said, “She fought so hard” and called her “a sweet and happy soul.”
Mack is survived by:
Parents: Kristen and Lindsay Klebenow
Siblings: Sister Kathryn Klebenow, brother Parker Mack (also an actor)
Grandparents: Lois and Larry Klebenow
Her Partner: Logan Lanier
Her final on-screen appearance and producer credit will be in the upcoming film Universal, scheduled for release posthumously.
Final Thoughts
Kelley Mack’s courage, creative ambition, and radiant spirit inspired colleagues and fans alike. While her life was far too short, her contributions, as an actress, filmmaker, and storyteller, leave an enduring legacy.