Actor Kelley Mack, known for her memorable performance as Addy in Season 9 of The Walking Dead, passed away last week at the age of 33. Her family confirmed the heartbreaking news on Tuesday, revealing that the actor died in her hometown of Cincinnati following a battle with glioma (a rare and often life-threatening brain tumour).
Mack’s acting journey began early, sparked by a childhood birthday gift – a mini video camera. That spark led to appearances in commercials and later a standout debut performance in The Elephant Garden, a film that earned the Student Visionary Award at the 2008 Tribeca Film Festival. She went on to graduate from Chapman University’s Dodge College of Film in 2014 with a degree in cinematography.
Over the years, Mack built a solid TV and film career. In addition to The Walking Dead, she played Penelope Jacobs in Chicago Med and appeared in FOX’s 9-1-1. Her film credits include Broadcast Signal Intrusion, Delicate Arch, and the upcoming Universal. She also pursued screenwriting, working on several feature-length scripts with her mother, including On The Black, a baseball drama inspired by her grandparents’ college years.
Her death has drawn attention to glioma, the tumour that ultimately claimed her life.
Kelley Mack Death Reason: Actress Dies Of Glioma
Glioma is a type of tumour that starts in the glial cells – supportive cells in the brain and spinal cord. It is the most common kind of primary brain tumour, with varying degrees of severity depending on its type and grade. According to the Cleveland Clinic, “Gliomas are malignant (cancerous), but some can be very slow growing.”
Gliomas are classified into several types:
1. Astrocytomas (including the aggressive glioblastoma)
2. Oligodendrogliomas (typically slower-growing)
3. Ependymomas
4. Mixed gliomas
The World Health Organization (WHO) grades them from I to IV. Low-grade gliomas (Grades I–II) tend to grow slowly and are sometimes treatable with surgery. High-grade types, especially Grade IV glioblastomas, are highly aggressive and often life-threatening.
How Life-Threatening Is Glioma?
Gliomas can be extremely serious. While low-grade tumours may be manageable for years, high-grade gliomas progress quickly and can significantly affect brain function. Symptoms like severe headaches, seizures, memory loss, and vision problems often mark the early signs of the disease.
Treatment typically involves a combination of surgery, radiation therapy, and chemotherapy. In some cases, targeted therapies or immunotherapy are also used. Despite medical advances, high-grade gliomas remain difficult to cure, and long-term survival is rare.
Kelley Mack Dies Of Glioma: What Do Patients Experience?
A glioma diagnosis can be emotionally devastating. Patients often undergo brain scans, biopsies, and extensive treatment. Many face physical and cognitive challenges, lifestyle changes, and emotional distress. Rehabilitation, regular monitoring, and support from loved ones are key parts of their journey.
Mack is survived by her parents Kristen and Lindsay Klebenow, siblings Kathryn and Parker, and grandparents Lois and Larry Klebenow. Her legacy lives on through her work and the memories she created with her family, friends, and fans.