Kelley Mack Dead at 33: Walking Dead Actress Lost to Cancer
I Just Found Out Kelley Mack Passed Away and I Can't Stop Thinking About Butterflies
I was mindlessly scrolling through my phone this morning when I saw the news. Kelley Mack. Gone. 33 years old.
I had to read it twice. Then I put my phone down and just sat there for a minute, coffee getting cold in my hands.
The Diagnosis That Changed Everything
Last Thanksgiving, while most of us were worried about turkey and family drama, Kelley was in an emergency room getting MRIs that would change her life. What started as back pain – the kind we all ignore and push through – turned out to be something terrifying: a tumor in her spinal cord.
She wrote about it so honestly on social media. How she'd been sleeping in a recliner for a month because lying down hurt too much. How the shooting pains in her legs got worse. Reading her posts now, knowing how it ended, makes my chest tight.
The clinical name for what she had was diffuse midline glioma. I had to look it up. It's one of those cancers that doesn't play fair – aggressive, fast-moving, stealing pieces of you as it grows. After her biopsy, she lost most of the use in her right leg, and a lot in her left. This vibrant, active woman who loved hiking and playing tennis suddenly needed a walker and wheelchair.
But here's what gets me: she kept sharing. Kept updating. Kept being real about what was happening. That takes a kind of courage I'm not sure I'd have.
More Than Just "That Girl from The Walking Dead"
I'll be honest – I first knew Kelley as Addy from The Walking Dead. Five episodes in Season 9, playing one of the people captured by the Whisperers. If you watched the show, you know that storyline was intense. Those episodes where her character was trying to survive, not knowing if she'd make it...
God, the irony hurts now.
But Kelley was so much more than one role. This morning, after reading the news, I went down a rabbit hole of her work. Did you know she was the voice match for Gwen Stacy in Spider-Man: Into the Spider-Verse? Yeah, THAT Spider-Verse. The one that made us all cry and won an Oscar. When Hailee Steinfeld wasn't available for certain scenes, it was Kelley's voice bringing Gwen to life.
I rewatched some scenes on YouTube. Knowing it's partially her voice makes them hit different now.
She Was Creating Until the End
What really got me was learning about Universal, her final project. Just a few weeks ago – WEEKS – she was posting about its premiere at the Chinese Theatre. "A small, down-to-earth film about huge, out-of-this-world concepts," she called it.
She was an executive producer on it. Starred in it. Was promoting it while dealing with everything else. The premiere is still coming up, and now it'll be a memorial screening. I don't know how her co-star and collaborator Stephen Portland is going to get through that.
She wasn't just in front of the camera either. The woman wrote, directed, edited. She produced A Knock at the Door, which won awards at horror film festivals. She was behind the camera for other projects. At 33, she'd built a career most actors would need several lifetimes to achieve.
The Girl from Cincinnati Who Made It
Kelley wasn't born into Hollywood. She was from Cincinnati, started with commercials as a kid like so many actors do. But get this – her real passion sparked when she got a mini video camera as a birthday gift. How perfectly full-circle that her life would be about creating stories through a lens.
Her first real film role was at 16, and she won an acting award from Tisch. Tisch! At 16! The film won at Tribeca. Can you imagine being a teenager from Ohio and suddenly you're winning awards at Tribeca?
She'd been in LA for 11 years, building her life, her career. She did commercials for brands we all know – heard a Budweiser ad lately? A Chick-fil-A spot? Might have been her voice. Even did a Hyundai commercial in 2024, right before the diagnosis.
The Person Behind the Performances
Her sister Kathryn's tribute destroyed me. She called Kelley a "tough SOB" and talked about how brave she was, "especially when she decided to make the leap to be reunited with God."
That phrasing – "decided to make the leap" – suggests Kelley had some control at the end, that she chose her moment. There's something both heartbreaking and powerful in that.
Her family painted a picture of someone who grabbed life with both hands. College tennis player. Hiker. Pickleball enthusiast (of course she played pickleball, it's so wonderfully random and specific). She played piano, loved to travel, went biking.
This wasn't someone who just acted for a living. This was someone who LIVED.
The Butterfly Thing Is Wrecking Me
Okay, this is the part where I completely lost it. Her family says Kelley has been visiting loved ones as butterflies. Different butterflies, appearing to different people.
I'm not usually one for signs and symbols, but there's something so perfect about this. Butterflies go through complete transformation. They're delicate but determined. They bring beauty wherever they land, even if it's just for a moment.
Is it real? Does it matter? If it brings comfort to the people missing her, then it's real enough.
Why This Hurts
I think what's hitting me hardest is the timing. 33 years old. She was supposed to have decades more. More roles, more productions, more hikes and pickleball games and piano sessions. More time to be that bright, fervent light her family described.
Instead, she got 11 months from diagnosis to the end. 11 months where she kept working, kept creating, kept living as fully as her body would allow.
There's going to be a memorial service on August 16th in Glendale, Ohio, where she's from. Then a celebration of life in LA for her industry friends. I imagine both will be packed. How could they not be?
What She Leaves Behind
Kelley's gone, but her work isn't. Every time someone watches The Walking Dead Season 9, she's there. Every time a kid watches Spider-Verse and falls in love with Gwen Stacy, part of Kelley is speaking to them. Every commercial, every short film, every project she produced – they're all still here.
But more than that, she leaves behind the example of how to face the unthinkable. She shared her journey, not for pity, but for connection. She kept working not because she had to, but because creating was who she was. She loved fully – her family, her boyfriend Logan, her friends, her craft.
The Reality of Glioma
I had to educate myself about what killed her. Central nervous system glioma. It attacks the glial cells in the brain and spinal cord. It's rare, aggressive, and cruel. The kind of cancer that doesn't give you time to prepare, just takes and takes until there's nothing left to take.
By talking about it publicly, Kelley did what artists do – she took her pain and transformed it into something that could help others. Maybe someone will read her story and push for that MRI they've been putting off. Maybe researchers will get more funding. Maybe another patient will feel less alone.
Sitting With This
It's afternoon now. I've written and rewritten this piece multiple times, trying to capture what I'm feeling. The thing is, I didn't know Kelley personally. But I knew her work, and through her final posts, I got a glimpse of her spirit.
She was just a year younger than me. Had the kind of career I'd dreamed about when I was younger. Was building something beautiful in the entertainment industry. And then, back pain. Shooting pains. A recliner instead of a bed. An MRI that changed everything.
Life is so stupidly fragile.
Final Thoughts
Tomorrow, when I inevitably see a butterfly, I'm going to think of Kelley Mack. I'm going to remember that she faced something terrifying with grace and honesty. That she kept creating until she couldn't. That she was loved so deeply her family sees her in every delicate wing that passes by.
Rest easy, Kelley. Thank you for the stories you told, the characters you brought to life, and the example you set. The entertainment world is dimmer without you, but heaven is brighter for having you.
And to her parents Kristen and Todd, her siblings Kathryn and Parker, her grandparents Lois and Larry, and her boyfriend Logan – I'm so sorry. She was clearly extraordinary, and the world knowing that doesn't make losing her any easier.
33 years. It wasn't enough. But damn, did she make them count.
If you're dealing with persistent pain or unusual symptoms, please don't wait. Get checked. Kelley's story reminds us that tomorrow isn't guaranteed, but also that sharing our struggles can help others. If you want to honor her memory, maybe that's how – by taking care of yourself and being open about your journey, whatever it might be.
FAQ Section
Q: What type of cancer did Kelley Mack have?
A: Kelley Mack was diagnosed with central nervous system glioma, specifically diffuse midline glioma, which is a rare and aggressive form of brain cancer that affects the glial cells of the brain and spinal cord.
Q: What was Kelley Mack's most famous role?
A: Kelley Mack was best known for playing Addy in five episodes of Season 9 of AMC's The Walking Dead (2018-2019), though she also provided voice work for Gwen Stacy in the Oscar-winning Spider-Man: Into the Spider-Verse.
Q: When and where did Kelley Mack pass away?
A: Kelley Mack passed away peacefully on August 2, 2025, in her hometown of Cincinnati, Ohio, at the age of 33, surrounded by her mother Kristen and aunt Karen.
Q: What other TV shows did Kelley Mack appear in?
A: Besides The Walking Dead, Kelley made guest appearances on 9-1-1, Chicago Med (as Penelope Jacobs), and Schooled (the Modern Family spinoff).
Q: Did Kelley Mack work behind the camera as well?
A: Yes, Kelley was also a producer, writer, and director. She produced the award-winning short film A Knock at the Door (2016), wrote and directed Positive (2015), and served as executive producer on her final film Universal (2025).
