By Sachin Shankar Yadav 
After battling a rare and aggressive brain cancer called diffuse midline glioma, a subtype of astrocytoma that affects the central nervous system, including the brain and spinal cord, actress Kelley Mack, best known for her role as Addy in Season 9 of “The Walking Dead,” tragically died at the age of 33. Months before she passed away in her hometown of Cincinnati, Ohio, on August 2, 2025, she received a diagnosis in January 2025.
She first experienced chronic lower back pain in late 2024, which later developed into neuropathic itching and excruciating shooting pains in her back and legs. An abnormal mass in her spinal cord was discovered during an emergency MRI in late 2024. She lost most of her left leg and her right leg’s mobility following spinal cord biopsy surgery, necessitating a wheelchair and walker.
A very aggressive tumor that grows out of control in glial cells that support nerve function is called diffuse midline glioma. The location of the tumor may affect the symptoms, but they frequently include headaches, vision issues, weakness, loss of balance, and trouble speaking. Despite the availability of radiation, chemotherapy, and surgery, this cancer is exceedingly uncommon, challenging to treat, and has a poor prognosis.
In order to raise awareness of this uncommon cancer, Kelley publicly shared her health journey with her fans. Her sister Kathryn posted heartfelt remarks about Kelley being a “bright, fervent light” that touches her loved ones even after death, and her mother Kristen and aunt Karen were there when she passed away quietly.
In addition to her roles on “The Walking Dead,” Kelley voiced characters in the animated movie “Spider-Man: Into the Spider-Verse,” “Chicago Med,” and “9-1-1.” Her struggle raised awareness of diffuse midline glioma and sparked calls for further study of this debilitating condition.
There are plans to celebrate and remember her life in Ohio and then in Los Angeles.
You should be able to write a sensitive and educational blog post about Kelley Mack’s life, career, valiant fight against a rare brain cancer, and her enduring legacy with the help of this thorough information.