Kelley Mack, Beloved Actress from The Walking Dead, Dies at 33

In early August 2025, the entertainment world was saddened to learn of the passing of Kelley Mack—a talented actress and producer best known for her role as Addy on The Walking Dead. At just 33 years old, she lost her battle with a rare brain and spinal cord tumor called diffuse midline glioma. Mack passed away peacefully on August 2 in Cincinnati, surrounded by close family, including her mother and aunt.

Her family formally shared the news via an emotional Instagram post, describing her as “a bright, fervent light” whose spirit had uplifted many. They wrote that since her transition, she had appeared to loved ones “in the form of various butterflies,” a poetic homage to her presence.

From Cincinnati to Hollywood: A Passion for Storytelling

Born Kelley Lynne Klebenow in Cincinnati, Ohio, she discovered a love for storytelling early in life. Her interest was sparked by a birthday gift—a video camera—that propelled her into performing. After graduating from Hinsdale Central High in 2010, she earned a degree in cinematography from Chapman University’s Dodge College in 2014.

Over the following decade, Mack built a diverse portfolio with roles across television, film, and commercials. She appeared in early projects like short films and miniseries such as Unusual Suspects, Grayson: Earth One, and Not Your Average Joe. Her TV appearances included standout roles on FOX’s 9‑1‑1 in 2019 and Chicago Med in 2022, where she played Penelope Jacobs. She also worked in high-profile ads, featured in commercials for brands like Dr. Pepper, Budweiser, Dairy Queen, Ross, Chick-fil-A, and Rakuten.

A Defining Role on The Walking Dead

Mack’s most widely recognized role came in season nine of AMC’s The Walking Dead, where she portrayed Addy for five episodes. Her performance resonated with fans and peers alike, earning her a place in the beloved zombie franchise.

Off-camera, she lent her voice to projects such as Spider-Man: Into the Spider-Verse in 2018—acting as a voice match for Hailee Steinfeld’s Gwen Stacy—and appeared in a 2024 Hyundai Ioniq commercial. Her final feature film, Universal, premiered in June 2025. Mack not only starred in the film but also served as an executive producer. Her social media post about its premiere reflected her pride in the project, calling it a “small, down‑to‑earth film about huge, out‑of‑this‑world concepts.”

A Public Battle with Glioma

In September 2024, Mack was diagnosed with diffuse midline glioma, a rare and aggressive tumor affecting the central nervous system. By early 2025, she had shared her diagnosis and treatment journey on social media. She described symptoms including excruciating back pain, leg numbness, and eventual loss of mobility, requiring assistance like a walker or wheelchair.

Despite her illness, Mack maintained candid communication with her followers, documenting her experiences with treatment and the challenges she faced. Her transparency resonated deeply with fans and fellow industry members.

Tributes from Colleagues and Fans

Responses poured in from across the entertainment world. Filmmaker Michael E. Satrazemis, who collaborated with her on The Walking Dead, remembered her as “a bright light on every level.” Actor Gustavo Gomez, who portrayed Marco on the show, shared: “Your bright light will always shine on.” Anthony Michael Lopez, another co-star, described her as “sweet and happy soul,” praising her courage and dedication.

Her authenticity, creativity, and kindness left a lasting impression on those who knew her personally and professionally.

Life Beyond the Camera

Kelley Mack’s loved ones also celebrated her life outside of film and TV. She was a passionate storyteller, a talented pianist, and a lover of outdoor activities including hiking, biking, trekking, and pickleball. She also deeply enjoyed traveling. Her diverse interests and warm nature enriched the lives of those around her.

Honoring Her Memory

A remembrance gathering is scheduled for August 16 in her native Cincinnati, followed at a later date by a celebration of life in Los Angeles—where she lived and worked for more than a decade.

Mack is survived by her mother Kristen, father Lindsay, sister Kathryn, brother Parker (also an actor), grandparents Lois and Larry, and her partner Logan. Her enduring legacy lives on through her family, fans, and the artistic contributions she made across screen and stage.

In the Spotlight: Kelley’s Legacy

Kelley Mack’s journey—marked by determination, creativity, and heartfelt connection—made her more than a performer. Her impact reached beyond her roles, as she inspired many with her openness, sincerity, and passion for storytelling. Though her life ended too soon, her spirit continues to occupy every memory, project, and tribute shared by fans and collaborators.

We remember Kelley not just for what she created, but for who she was: a bright, generous presence whose light touched many lives.