Hollywood Actress Kelley Mack Dies at 33 After Battle with Rare Cancer

Hollywood is grieving the loss of Kelley Mack, a gifted actress best known for her roles in acclaimed television series such as The Walking Dead and Chicago Med. She passed away peacefully on August 2, 2025, at the age of 33, following a courageous battle with a rare form of cancer known as diffuse midline glioma.

Born Kelley Klebenow in Cincinnati, Ohio, Mack captivated audiences with her portrayal of Addy in Season 9 of The Walking Dead, and Penelope Jacobs in Season 8 of Chicago Med. Her versatility extended beyond live-action roles—she also lent her voice to Gwen Stacy in the Oscar-winning animated film Spider-Man: Into the Spider-Verse.

In January 2025, Mack publicly shared her diagnosis, detailing the physical challenges she faced, including loss of mobility due to a spinal cord biopsy. Despite undergoing proton radiation therapy and showing signs of recovery, her condition ultimately proved fatal.

Her family announced her passing in a heartfelt statement, describing her as “a bright, fervent light” and noting that she died surrounded by loved ones. They shared that Kelley had “already come to many of her loved ones in the form of various butterflies,” a symbol of her enduring spirit.

A remembrance ceremony will be held on August 16 in Glendale, Ohio, with a second celebration of life planned in Los Angeles.