Kelley Mack, best known for her role as Addy in AMC’s post-apocalyptic series “The Walking Dead”, has passed away at the age of 33 after a courageous fight against glioma, a rare form of brain cancer. Her death has deeply saddened fans, friends, and colleagues across the entertainment industry.
Remembering Kelley Mack: A Shining Light in Television
Kelley Mack, whose real name was Kelley Klebenow, passed away peacefully on August 3, 2025, in her hometown of Cincinnati, Ohio. She had been battling glioma, a central nervous system cancer that affects the brain or spinal cord, for over a year. Her family announced her death in a heartfelt statement published on the platform CaringBridge.
“We are heartbroken to share the passing of our dear Kelley,” the statement read. “A bright, passionate light has returned to the stars. She went ahead of us to the place we all eventually go.”
The news of her passing was later confirmed via her official Instagram page alongside a recent photo, showing her smiling despite her ongoing medical challenges.
Kelley Mack’s Rise to Fame and Impact on TV Audiences
Mack rose to prominence through her performance as Addy, a survivor and member of the Hilltop Colony in Season 9 of The Walking Dead. Her character was admired by fans for her resilience and determination in the zombie-infested world of the popular AMC series.
Beyond The Walking Dead, Kelley Mack had accumulated over 35 acting credits and 5 producer credits throughout her career. She starred in notable television shows such as:
- Chicago Med (Season 8) as Penelope Jacobs
- FOX’s 9-1-1 in various guest roles
- Several indie films and short films, which showcased her talent beyond mainstream productions.
Kelley’s authenticity, depth, and emotional range made her a beloved presence on-screen, and her contributions to the entertainment industry leave a lasting legacy.
Her Brave Battle with Glioma: Misdiagnosed Back Pain Turned Life-Threatening
In a personal Instagram post made in January 2025, Mack detailed the early symptoms of her illness. She initially believed her persistent back pain was due to a slipped disc or spinal strain. However, as the pain intensified and strange sensations—like nerve-induced itching in her right thigh—developed, she sought further medical attention.
After extensive testing in September 2024, doctors diagnosed her with a rare and aggressive form of glioma, a cancer originating in the glial cells of the central nervous system. Despite the devastating diagnosis, Mack remained optimistic and frequently updated her followers with courageous and inspiring posts.
One particularly poignant hospital photo shows her giving a thumbs-up and smiling, despite the reality of her situation. Her strength during those moments resonated with thousands who followed her journey.
Colleagues Pay Tribute to a “Gentle Soul”
Her The Walking Dead co-stars, friends, and fans poured out their grief online. Actress Alanna Masterson, who played Tara Chambler on the show, shared a touching message:
“What an incredible human. I was proud to fight beside her in our finale. Her heart, talent, and spirit will never be forgotten.”
Dozens of fans expressed heartbreak, recalling Addy’s character arc and Mack’s real-life bravery. Her authenticity and kindness on set left a deep impression on everyone who had the privilege to work with her.
A Stark Reminder of Rare Cancers: What Is Glioma?
Gliomas are a type of tumor that starts in the glial cells of the brain or spinal cord. These tumors vary in severity and type, but central nervous system gliomas are considered rare and often difficult to treat. Symptoms may be subtle at first—such as unexplained back pain or nerve issues—and early diagnosis is critical.
Kelley Mack’s story serves as a somber reminder that persistent pain and neurological symptoms should never be ignored. Her openness about her health challenges helped bring awareness to an illness that often goes undetected until it is in advanced stages.
Honoring Kelley Mack’s Legacy
Kelley Mack was more than an actress—she was a storyteller, a fighter, and a beacon of strength. Her dedication to her craft, her fight against a vicious illness, and her ability to inspire others even in her darkest days have left an indelible mark.
She is survived by her loving family, countless friends, and fans around the world who will remember her for the joy she brought to the screen—and the courage she displayed behind the scenes.
“Her light will continue to shine through the lives she touched and the stories she helped tell,” her family said in closing.
