In Memory of Kelley Mack: A Bright Star Gone Too Soon

The entertainment world is reeling from the heartbreaking news of Kelley Mack’s passing, announced just thirty minutes ago. At the tender age of 33, the talented actress, best known for her role as Addy, a resilient resident of the Hilltop Colony in Season 9 of AMC’s The Walking Dead (2018–2019), left an indelible mark on the hearts of fans and colleagues alike. Her untimely death, caused by a courageous battle with diffuse midline glioma, a rare and aggressive form of brain cancer, has left a void in the industry and among those who cherished her vibrant spirit.
Kelley Mack, born Kelley Lynne Klebenow on July 10, 1992, in Cincinnati, Ohio, was a multifaceted artist whose passion for storytelling illuminated every project she touched. From a young age, her love for the arts was evident. A childhood gift of a mini video camera sparked a lifelong devotion to filmmaking, leading her to study cinematography at Chapman University’s Dodge College of Film and Media Arts, where she earned her bachelor’s degree in 2014. This foundation fueled her remarkable career, which spanned acting, producing, screenwriting, and voice-over work, earning her 35 acting credits and five producer credits.
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Mack’s portrayal of Addy in The Walking Dead was a standout, showcasing her ability to bring depth to a post-apocalyptic world. Appearing in five episodes, her character, a stoic yet gentle Hilltop resident, resonated with audiences, particularly in her emotional arc involving a crush on Henry (Matt Lintz) before meeting a tragic end at the hands of Alpha and the Whisperers. Her performance, though brief, was memorable, cementing her as a beloved figure in the show’s expansive ensemble.
Beyond The Walking Dead, Mack’s versatility shone through in roles on 9-1-1 (2019), where she made a guest appearance, and Chicago Med (2022), where she portrayed Penelope Jacobs. Her film credits included Broadcast Signal Intrusion (2021) alongside Harry Shum Jr., Delicate Arch (2024), and the recently released Universal (2025), where she not only starred as Ricky but also served as an executive producer. Her voice-over work was equally impactful, notably as the voice match for Hailee Steinfeld’s Gwen Stacy in the Oscar-winning Spider-Man: Into the Spider-Verse (2018) and a 2024 Hyundai Ioniq commercial. Mack’s commercial work, including spots for Dr Pepper, Budweiser, and Chick-fil-A, further highlighted her charisma and range.
In September 2024, Mack bravely shared her diagnosis of diffuse midline glioma, a rare cancer affecting the brain and spinal cord. Despite undergoing aggressive treatment, including a biopsy that resulted in the loss of mobility in her legs, she remained a beacon of resilience. In January 2025, she posted on Instagram about her journey, detailing her use of a walker and wheelchair while celebrating small victories, like climbing stairs with the support of her boyfriend, Logan Lanier. Her updates reflected her unwavering positivity, inspiring fans and loved ones even in the face of immense challenges.
Mack’s family, including her parents Kristen and Lindsay, sister Kathryn, brother Parker (also an actor), and grandparents Lois and Larry, described her as a “bright, fervent light.” Her sister’s poignant Instagram post, shared shortly after her passing on August 2, 2025, in Cincinnati, spoke of Kelley’s peaceful departure surrounded by her mother and aunt Karen. “Kelley has already come to many of her loved ones in the form of various butterflies,” Kathryn wrote, a touching metaphor for her sister’s enduring presence. Tributes from colleagues, including The Walking Dead co-star Alanna Masterson and director Michael Satrazemis, poured in, celebrating her talent and warmth.
Outside of her professional achievements, Mack was an accomplished college tennis player, a lover of hiking, pickleball, biking, piano, and travel. Her vibrant personality, marked by a penchant for dark chocolate, country music, and a playful British accent, endeared her to all. A remembrance is planned for August 16 in Glendale, Ohio, with a Los Angeles celebration to follow, honoring her 11 years in the city.
Kelley Mack’s legacy is one of artistry, courage, and love. Her contributions to film and television, coupled with her fearless spirit, ensure that her light will continue to shine through the stories she told and the lives she touched. She will be deeply missed but forever remembered.