News broke Sunday that Hayden Panettiere had died at 36, and it hit a lot of people harder than they expected. Her rep confirmed the death to ABC News, calling her "an incredible light and a force of nature who brought immeasurable love and joy to all who knew her." No cause of death has been released.

For anyone who grew up online or in front of a TV in the 2000s, Panettiere was everywhere. She started as a child actor and worked her way through Remember the Titans, Raising Helen, Ice Princess and Scream 4 before landing the role that made her a household name: Claire Bennet, the indestructible cheerleader at the center of Heroes. She followed that up years later with Juliette Barnes on Nashville, a very different kind of star turn that showed off range a lot of former child actors never get the chance to prove they have.
Panettiere had also been candid about the harder side of fame, writing about it in a memoir, This Is Me: A Reckoning, that she released just this past May. That honesty is part of why the tributes pouring in feel personal instead of generic — people weren't just mourning a TV character, they were mourning someone who let fans see the real cost of growing up on camera.

Heroes was such a favorite of mine growing up. Hayden Panettiere did so much more than that but she was a major part of that show and was awesome. Always dealing with all sorts of issues sadly. 36 is way too young
Eric Hubbs' reaction captures the general mood: Heroes was a defining show for a lot of people in that era, and Claire Bennet was a huge part of why. Panettiere was the emotional anchor of a superhero ensemble that made "save the cheerleader, save the world" a genuine pop-culture catchphrase, and she did it as a teenager carrying a network drama alongside a much older cast.
There's no word yet on funeral arrangements or further details on her death, and given her rep's statement, it sounds like the family is still processing this in real time. For now, the tributes from people who grew up watching her — on Heroes, on Nashville, or in one of her earlier films — are the story, and 36 is a brutal age for any of it to end.