Image Credit: Getty Images Kelley Mack died at the age of 33 in August 2025 after battling a rare form of brain cancer. Her acting career had just gotten traction, with her performance in The Walking Dead being praised by fans. Mack's multi-talented nature led her to pursue different projects, and she promoted her upcoming film work during the last months of her life. Below, Hollywood Life explains the kind of cancer Mack was living with and what a glioma is. Who Was Kelley Mack? Mack was an actress, producer and voiceover artist.