At the time of her death, the Ohio-born actor had been actively promoting the independent sci-fi feature "Universal," in which she has a starring role.

Kelley Mack, famous for her roles on "The Walking Dead" and "Chicago Med" has died of cancer at age 33. Her sister, Kathryn, announced Mack's passing Tuesday on Mack's Instagram page. Mack died Saturday according to the post. She died of diffuse midline glioma, NBC News reported .