On August 2, 2025, Kelley Mack, a talented actress known for her role as Addy in The Walking Dead, passed away at age 33 in her hometown of Cincinnati, Ohio. Her family confirmed the news through a statement posted on her Instagram account on August 5, revealing that she succumbed to a rare and aggressive form of brain cancer, diffuse midline glioma. Mack’s vibrant career spanned television, film, commercials, and voice-over work, leaving a lasting mark on the entertainment industry. This article explores her life, achievements, health battle, and enduring legacy.
Early Life and Education
Born Kelley Lynne Klebenow on July 10, 1992, in Cincinnati, Ohio, Mack grew up in a family that nurtured her creative spirit. Her parents, Kristen and Lindsay Klebenow, supported her early passion for storytelling, sparked by a mini video camera she received as a childhood birthday gift. According to The Hollywood Reporter, Mack’s love for filmmaking developed through creating short videos, setting the stage for her future career.
Mack moved frequently during her childhood, living in Wyoming, Ohio; Mount Lookout, Ohio; Ellisville, Missouri; Avon, Connecticut; Charlotte, North Carolina; and Hinsdale, Illinois. She graduated from Hinsdale Central High School in 2010 and pursued higher education at Chapman University’s Dodge College of Film and Media Arts in Orange, California, earning a bachelor’s degree in cinematography in 2014. An accomplished college tennis player, Mack also enjoyed hiking, pickleball, biking, playing piano, and traveling, as noted in her obituary.
Breakthrough in Acting
Mack’s acting career began in childhood with commercial work, including ads for Dr. Pepper, Ross Stores, Dairy Queen, Chick-fil-A, and a Rakuten spot alongside her mother, Kristen. Her first major role came in 2008 as Chloe in the short film The Elephant Garden, which earned her an Acting Award from the Tisch School of the Arts and a Student Visionary Award at the Tribeca Film Festival, per Deadline. This early success highlighted her versatility and promise as a performer.
Her breakthrough role was as Addy, a resident of the Hilltop Colony, in five episodes of The Walking Dead’s ninth season (2018-2019). Though brief, her performance in the AMC series, particularly in the season finale where her character faced the Whisperers, resonated with audiences. Mack’s ability to bring depth to ensemble casts earned her recognition, as reported by The Independent.
Diverse Roles Across Film and Television
Mack amassed 35 acting credits and five producer credits over her career, showcasing her multifaceted talent. She appeared as Penelope Jacobs in season 8 of Chicago Med (2022) and made a guest appearance on 9-1-1 (2019). Her film roles included Alice in the psychological thriller Broadcast Signal Intrusion (2021) opposite Harry Shum Jr., Wilda in Delicate Arch (2024), and a starring role as Ricky in the upcoming comedy-drama Universal (2025), where she also served as an executive producer alongside Joe Thomas and Rosa Robson.
Mack’s voice-over work included serving 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. She also starred in short films and miniseries, such as Unusual Suspects (2015), Grayson: Earth One (2015), Not Your Average Joe (2016), and Unscrewed (2016). Her producing credits included the 2016 short A Knock at the Door, which won a Festival Award at the Atlanta Horror Film Festival, and the 2015 short Positive, which she wrote, directed, and edited.
Battle with Glioma
In September 2024, Mack began experiencing persistent lower back pain, initially mistaking it for a slipped disc. As symptoms worsened, including nerve-related itching and debilitating leg pain, an emergency MRI in November 2024 revealed an abnormal mass on her spinal cord. She was diagnosed with diffuse midline glioma (DMG), a rare and aggressive brain cancer that affects the brain or spinal cord, primarily in children but also in adults, per the Mayo Clinic.
Mack underwent aggressive treatment, including proton radiation completed in April 2025, as shared on her CaringBridge page. A biopsy surgery on her spinal cord resulted in the loss of mobility in her right leg and partial loss in her left, requiring her to use a walker and wheelchair. Despite these challenges, Mack remained resilient, sharing updates on Instagram, including a March 2025 post celebrating her progress walking stairs with the support of her boyfriend, Logan Lanier.
On August 2, 2025, Mack passed away peacefully in Cincinnati, surrounded by her mother, Kristen, and aunt, Karen, according to a family statement on CaringBridge. Her sister, Kathryn, described her as a “bright, fervent light” and noted symbolic visits from butterflies, believed to represent Mack’s spirit.
Tributes from Colleagues and Fans
The entertainment community mourned Mack’s passing, with tributes pouring in from The Walking Dead co-stars and collaborators. Alanna Masterson, who played Tara Chambler, wrote on Instagram, “What an incredible human. So proud to have fought alongside her in our final episode together.” Director Michael E. Satrazemis, who worked with Mack on The Walking Dead, called her “a bright light on every level,” per The Hollywood Reporter. Actor Gustavo Gomez added, “This is heartbreaking. I feel so lucky that our paths crossed. Your bright light will always shine on.”
Fans on X expressed grief, praising Mack’s talent and warmth. Some posts inaccurately linked her illness to vaccination status, but her family and agent, Julie Smith, confirmed her cause of death as glioma, with no evidence supporting other claims, per CNN. A remembrance is scheduled for August 16, 2025, at the Glendale Lyceum in Glendale, Ohio, with a Los Angeles celebration of life planned for a later date.
Personal Life and Interests
Mack’s family remembered her as a vibrant soul who cherished storytelling, collaboration, and time with loved ones. She was an avid sports enthusiast, enjoying fantasy football, and had a fondness for dark chocolate, bourbon, popcorn, country music, and speaking in a British accent. A lifelong smoker, Mack also loved animals, both real and stuffed, reflecting her playful spirit.
She is survived by her parents, Kristen and Lindsay Klebenow; her sister, Kathryn; her brother, Parker, also an actor; her grandparents, Lois and Larry Klebenow; and her boyfriend, Logan Lanier. Her family emphasized her creativity and unwavering support for those around her, noting her ability to inspire through her work and personal connections.
Legacy in Film and Beyond
Mack’s career, though cut short, left a significant impact. Her role in The Walking Dead introduced her to a global audience, while her work in independent films and producing showcased her versatility. Her final project, Universal, set to screen at the Portland Festival of Cinema, Animation and Technology on August 10, 2025, and the Chain NYC Film Festival on August 11, 2025, reflects her commitment to storytelling.
Her family’s statement on Instagram highlighted her legacy: “Her vibrant spirit, creative passion, and dedication to storytelling left an indelible mark on those who knew her and the audiences she captivated.” Mack’s contributions to film, television, and voice-over work, combined with her warmth and resilience, ensure her memory endures in the industry and among fans.
Industry Context and Future Projects
Mack’s passing comes amid a challenging period for the entertainment industry, with other young talents, such as Sophie Nyweide and Millena Brandão, also lost in 2025, per People. Her work on Universal underscores the growing influence of independent cinema, where she thrived as both an actress and producer. The film’s festival screenings highlight her lasting contributions, even posthumously.
Conclusion
Kelley Mack, born Kelley Lynne Klebenow, died on August 2, 2025, at age 33 in Cincinnati, Ohio, after battling diffuse midline glioma, a rare brain cancer. Known for her role as Addy in The Walking Dead’s ninth season, she amassed 35 acting credits, including Chicago Med, 9-1-1, Broadcast Signal Intrusion, and the upcoming Universal, where she also served as executive producer. Born in 1992, Mack graduated from Chapman University and began her career in commercials, later earning awards for her work in short films. She passed away surrounded by family, with a remembrance planned for August 16 in Ohio and a future Los Angeles memorial. Survived by her parents, siblings, grandparents, and boyfriend, Mack’s legacy endures through her vibrant contributions to film and television.
Sources & References:
- The Hollywood Reporter
- The Independent
- CNN
- Deadline
- People
- USA Today
- The Times of India
- Euronews
- The Week
