The Walking Dead and Chicago Med actress Kelley Mack (née Klebenow) passed away peacefully on August 2 at age 33 after a battle with glioma of the central nervous system. Her family shared that she died surrounded by her mother Kristen and aunt Karen in her native Cincinnati, Ohio, and noted that Kelley’s spirit has already comforted loved ones “in the form of various butterflies.” A life celebration will be held in Ohio next week, with details available via a formal two-page announcement linked in her social media tribute.

Best known to genre fans as Addy in Season 9 of The Walking Dead, Mack built an 11-year career in Los Angeles with over 35 screen credits. In addition to her zombie-apocalypse work, she portrayed Penelope Jacobs on Chicago Med and appeared in procedural drama 9-1-1. Her résumé also included commercials for brands like Dr. Pepper, Ross, Dairy Queen, Chick-fil-A, and most recently Rakuten alongside her mother.

Colleagues and fans flooded her Instagram tribute with heartfelt condolences. Actor Anthony Michael Lopez remembered Kelley as a “sweet and happy soul” who “fought so hard,” while The Walking Dead director Michael E. Satrazemis called her “a bright light on every level.” Co-star Gustavo Gomez added, “Your bright light will always shine on.” Their messages underscore how warmly she was regarded on and off set.

A graduate in cinematography, Kelley was celebrated for her warmth, creativity, and unwavering support of those around her. Beyond acting, she loved hiking, playing pickleball, biking, piano, and travel. Though gone too soon, her family hopes her legacy of storytelling, collaboration, and genuine kindness will continue to inspire all who knew her.