Kelley (Kelley Lynne Klebenow) Mack, the actress best known for playing Addy on The Walking Dead , sadly passed away in August 2025 at the age of 33 after a battle with cancer of the central nervous system.

Quick Scoop: What happened to Kelley Mack?

Kelley Mack died on August 2, 2025, in Cincinnati, Ohio, surrounded by close family, after being diagnosed with a glioma, a rare and aggressive tumor of the central nervous system. Her family and representatives described her passing as peaceful but very unexpected, because she had still been auditioning and working just weeks before her death.

Her family’s public statement described her as a “bright, fervent light” and shared that she had been facing an “extremely rare” diffuse midline glioma, a form of astrocytoma cancer that she had spoken about on Instagram earlier in 2025. Fans and colleagues from shows like The Walking Dead , Chicago Med , 9-1-1 , and films such as Broadcast Signal Intrusion and Delicate Arch posted tributes mourning how young she was and how much impact she had in a relatively short career.

Her family organized a celebration of her life in mid‑August 2025 in Ohio, with another remembrance planned in Los Angeles, where she had lived and worked for over a decade. Online, communities like The Walking Dead fan forums and social media threads filled with messages of grief, memories of her character Addy, and condolences to her loved ones.

Information gathered from public forums or data available on the internet and portrayed here.