Image Credit: Getty Images Kelley Mack was a dedicated and hard-working actress, producer and voiceover artist best known for playing Addy in The Walking Dead. But Mack's life was cut short in 2025 after a months-long cancer battle. She was only 33 when she died, and her sister penned a heartfelt Instagram caption announcing her death. "Kelley passed peacefully on Saturday evening with her loving mother Kristen and steadfast aunt Karen present," the post read.