Mack, who played Hilltop Colony resident Addy on the hit show, died on Saturday night in Cincinnati.

A remembrance service for her is planned for August 16 in her native Ohio, with a further celebration of life to be held at a later date in Los Angeles, where she had spent most of her adult life.

In a statement, Mack's family said: “Her vibrant spirit, creative passion, and dedication to storytelling left an indelible mark on those who knew her and the audiences she captivated through her work."

Before her breakthrough role in The Walking Dead, Mack appeared in a number of shorts and TV miniseries such as Unusual Suspects, Grayson: Earth One, Not Your Average Joe, and Unscrewed.

She also appeared in episodes of 9-1-1 and Chicago Med and even starred as Hailee Steinfeld's voice match in Spider-Man: Into the Spider-Verse.

Just weeks before her death, Mack shared a post to Instagram promoting her final film, Universal. She wrote: “It’s a small, down-to-earth film about huge, out-of-this-world concepts, and we’re looking forward to sharing it with you."

According to her family, Mack died after being diagnosed with cancer, specifically a glioma of the central nervous system.

She was just 33.