Kelley Mack—the actress who appeared as Addy on season nine of The Walking Dead—died following a battle with a rare form of cancer. She was 33.
The TV community has lost a shining star.
Kelley Mack—known for her recurring roles as Addy on The Walking Dead, as well as her guest spots on 9-1-1 and Chicago Med—died on Aug. 2, her family shared on social media. She was 33.
“It is with indelible sadness that we are announcing the passing of our dear Kelley,” her sister Kathryn wrote in an Aug. 5 Instagram post. “Such a bright, fervent light has transitioned to the beyond, where we all eventually must go.”
Noting that Kelley (whose real name was Kelley Lynne Klebenow) passed away “peacefully” with her mother Kristen and aunt Karen by her side, the statement continued, “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.”
And Kathryn closed out her statement with a special note to all of her sister’s loved ones.
“She would want you all to know how much she loves you,” she said. “And 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.”
A memorial will be held for Kelley in her home state of Ohio on Aug. 16.
One year before her passing, Kelley had been undergoing treatment for a rare form of cancer called diffuse midline glioma, which is caused by a highly aggressive, cancerous brain tumor that develops in the midline structures of the brain, such as the brainstem, thalamus, and spinal cord.
“Due to the biopsy surgery on my spinal cord,” she shared on Instagram in January, “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.”
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Following the procedure, Kelley revealed that she had been making huge strides in her recovery, sharing a video of her walking about the stairs with the help of her boyfriend Logan.
“I’ve been up and down these stairs now 2x in the past few days,” she wrote on Instagram in March. “It’s a big deal for me. (Life has also had its ups and downs lately am I right lol).”
And while she may have been battling a difficult health journey, Kelley was still making major moves in her career, including starring in the upcoming film Universal alongside Rosa Robson and Joe Thomas.
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Indeed, her acting resume included 32 other credits, including playing Addy for five episodes during the ninth season of The Walking Dead in 2018 and starring opposite Harry Shum Jr. in 2024’s Mr. Manhattan.
For Kelley, her passion for the arts was born from a love of storytelling. As she explained in a 2022 Instagram, “I love acting so much and it warms me to know when others are touched by the stories I’m so lucky to be a part of sharing.”