Kelley Mack, an actress best known for her work on the horror series “The Walking Dead,” has died at age 33.

A representative for Mack confirmed her death to ABC News and said in a statement, “She will be so missed.”

In an online statement, Mack’s family said she died on Aug. 2 with her mother and aunt at her side following a battle with glioma, a type of tumor of the central nervous system.

“It is with indelible sadness that we are announcing the passing of our dear Kelley,” Mack’s family wrote in the statement, and also called her “a bright, fervent light.”

“Kelley has already come to many of her loved ones in the form of various butterflies 🦋 ❤️. She will be missed by so many to depths that words cannot express,” the statement added.

In a January Instagram post, Mack revealed she had been diagnosed with diffuse midline glioma, a rare type of cancer.

As an actor, Mack portrayed Addy during the ninth season of “The Walking Dead” and Penelope Jacobs in the eighth season of “Chicago Med,” which will return for its 11th season this fall. She was also known for her role as Alice in the horror film “Broadcast Signal Intrusion.”

Born Kelley Klebenow, Mack was a Cincinnati, Ohio, native and grew up in Ohio, North Carolina and Illinois, according to her family. She graduated from Chapman University in 2014 and lived and worked in Los Angeles for the past decade. She was the oldest of three children, including her sister, Kathryn, and brother Parker Mack, who is also an actor.

In addition to acting, Mack was also a producer, writer and voiceover artist, who provided the voice of Gwen Stacy for the hit film “Spider-Man: Into the Spider-Verse.”

Mack’s family said a “recognition and remembrance” of life for Mack will be held Aug. 16 in Glendale, Ohio, and that another celebration of life will be held in Los Angeles at a date yet to be determined.