Actress Kelley Mack, known for her roles in “The Walking Dead” and “Chicago Med,” died Saturday in her hometown of Cincinnati, Ohio.
Mack succumbed to a battle with glioma, a form of cancer that affects the central nervous system, according to a blog on health platform Caringbridge about her health journey.
She was 33.
“It is with indelible sadness that we are announcing the passing of our dear Kelley,” her sister, Kathryn Klebenow, revealed on Mack’s Instagram page Tuesday. “Such a bright, fervent light has transitioned to the beyond, where we all eventually must go.”
“Kelley passed peacefully on Saturday evening with her loving mother Kristen and steadfast aunt Karen present,” the Instagram post added. “Kelley has already come to many of her loved ones in the form of various butterflies. She will be missed by so many to depths that words cannot express.”
Mack, whose full name is Kelley Lynne Klebenow, said she first started noticing “persistent lower back pain” in October 2024.
Her health issues escalated the night before Thanksgiving when she went to the emergency room and underwent an MRI, which revealed “an abnormal mass” in her spinal cord.
In January, Mack was diagnosed with diffuse midline glioma, a rare tumor that begins in the brain or spinal cord, according to the National Cancer Institute.
“Due to the biopsy surgery on my spinal cord, I have lost the use of my right leg and most of my left leg, so I now get around with a walker and a wheelchair,” Mack said.
Mack was public about her recovery efforts on social media.
On March 26, she documented herself “re-learning how to walk” during her physical therapy as she walked up a set of stairs with support from a railing.
“Life has also had its ups and downs lately am I right,” Mack quipped.
Mack started acting in commercials as a kid and her first film role was in “The Elephant Garden,” which won the Student Visionary Award at the 2008 Tribeca Film Festival.
The Ohio native appeared in five episodes of “The Walking Dead” as Hilltop Colony resident “Addy” in season 9 of the hit post-apocalyptic horror series.
“I was only supposed to be in 2 episodes originally, so I was grateful to have been able to work on five of them and hadn’t anticipated that I’d stay on the show for too long,” Mack told Alternative Mindz in 2019.
Mack is survived by her mother and father, Kristen and Lindsay Klebenow, sister, Kathryn, brother Parker, and grandmother and grandfather Lois and Larry Klebenow.
Her funeral will be on August 16 in Glendale, Ohio.
“As her sister, I want you all to know how brave that tough SOB was, especially when she decided to make the leap to be reunited with God. I’m so f–king proud of her,” Kathryn wrote.
Aside from her role on “The Walking Dead,” Mack has produced a series of short films and appeared as a guest star on shows like “9-1-1” and “Chicago Med.”