9-1-1 and The Walking Dead star Kelley Mack dies at 33 after brave battle with rare and aggressive cancerous brain tumour

The entertainment industry is mourning the heartbreaking loss of actress Kelley Mack, who passed away on August 2 at just 33 years old. Known for her roles in The Walking Dead, 9-1-1, and Chicago Med, the talented star left a mark on both screen and soul.



Her family confirmed her death in a moving statement shared on social media, expressing the deep sorrow felt by all who knew her. Her sister, Kathryn, described her as a “bright, fervent light” who has now moved on to the beyond, a place we all eventually must go. Kelley died peacefully, with her mother and aunt by her side.

Kelley Mack fought a battle with immense courage

Kelley had been undergoing treatment for diffuse midline glioma, a rare and aggressive cancerous brain tumour that attacks the brainstem, thalamus, or spinal cord. Diagnosed just a year before her death, she faced her illness with remarkable bravery and vulnerability, openly documenting her journey.

9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack

( Image credit : 9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack )

In a January post, she had shared the devastating effects of a biopsy on her spinal cord that left her unable to use her right leg and most of her left. Despite needing a walker and wheelchair, Kelley never lost hope.

9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack

( Image credit : 9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack )

Kelley Mack struggled over the past few months

In March, she posted a video of herself walking up and down the stairs with the help of her partner, Logan, calling it a massive personal victory. She often reflected on her journey with humour and hope, showing incredible strength even in her darkest hours.

9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack

( Image credit : 9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack )

Even as her health declined, Kelley remained devoted to her craft. She had recently completed filming Universal alongside Rosa Robson and Joe Thomas, adding to her impressive list of 32 acting credits. Her performance as Addy in The Walking Dead Season 9 remains one of her most recognised roles.

9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack

( Image credit : 9-1-1 star Kelley Mack dies at 33 after battling brain tumour | Credit: Instagram/itskelleymack )

Kelley once shared that her passion for acting came from a love of storytelling, and she found great joy knowing her work touched others.

Her family shared that butterflies have appeared to several loved ones since her passing—a comforting sign that her spirit lives on. A memorial service in her honour will be held in Ohio on August 16.