Kelley Mack, known for playing the role of Addy in Season 9 of The Walking Dead, passed away on August 2 at the age of 33, her sister Kathryn Klebenow announced on Tuesday.

“It is with indelible sadness that we are announcing the passing of our dear Kelley. Such a bright, fervent light has transitioned to the beyond, where we all eventually must go,” Klebenow wrote on Instagram alongside a picture of Mack.

“Kelley passed peacefully on Saturday evening with her loving mother Kristen and steadfast aunt Karen present,” the post further reads.

“She would want you all to know how much she loves you. And as her sister, I want you all to know how brave that tough SOB was, especially when she decided to make the leap to be reunited with God. I’m so f****** proud of her,” Klebenow signed off.

Mack’s family said in a statement that she died in her hometown of Cincinnati after a battle with glioma of the central nervous system, Variety has reported.

Mack graduated from Hinsdale Central High School in 2010, and pursued a bachelor’s degree in cinematography from the Dodge College of Film at Chapman University back in 2014.

Mack made her acting debut with the film The Elephant Garden, which earned her an acting award from Tisch School of the Arts for her role. The film also won the Student Visionary Award at the Tribeca Film Festival in 2008.

Mack was best known for her work in TV series — particularly for playing Addy in Season 9 of The Walking Dead, Penelope Jacobs in Season 8 of Chicago Med and on FOX’s 9-1- 1. She also featured in films like Broadcast Signal Intrusion and Delicate Arch.

Mack also worked as a screenwriter with her mother, Kristen Klebenow. Her screenwriting credits include On The Black, a college baseball story set in the 1950s that is loosely based on her maternal grandparents' time studying at Ohio University.

The actress is survived by her mother and father, Kristen and Lindsay Klebenow, sister Kathryn, brother Parker, and grandparents Lois and Larry Klebenow.