Hayden Panettiere, troubled star of Heroes and Nashville, remembered as 'brave and brilliant soul'

Hayden Panettiere, who soared to fame two decades ago as a cheerleader with superpowers in the TV show Heroes and won country music success playing a singer on Nashville, has died. She was 36.

Police said Panettiere was found unresponsive in an apartment in Greenville, S.C., shortly before 2 p.m. Sunday. Life-saving measures were performed, but she was pronounced dead at the scene.

No cause of death has been determined and Panettiere's death remains under investigation. An autopsy found no signs of trauma and police said officers saw no signs of foul play.

"What an amazing talent you were … so gifted," wrote actress Viola Davis, who co-starred with Panettiere in the 2016 film Custody, on Instagram.

"Sending my love to Hayden and her family," wrote actor David Arquette, who worked with Panettiere on Scream 4, in an Instagram story. "She was such a brave and brilliant soul."

The television and film performer, who would have turned 37 on Friday, had been open about her private battles and wrote at length about them in the memoir This Is Me: A Reckoning, which came out in May.

She described lifelong scars from her early fame, and acknowledged being addicted to alcohol and enduring postpartum depression after the birth of her daughter with Ukrainian boxer Wladimir Klitschko in 2014.

"It is with profound sadness that we share the tragic passing of our beloved Hayden," her father, Skip Panettiere, said in a statement provided to ABC. "She was an incredible light and a force of nature who brought immeasurable love and joy to all who knew her — and to the millions who watched her on screen."

WATCH | Panettiere spoke publicly of post-partum depression:

A publicist for Panettiere did not provide any additional details in response to inquiries from The Associated Press and CBC News.

In her final Instagram post, dated July 27, Panettiere is seen in a black and white photo, smiling and winking alongside director and photographer Randall Slavin.

"Good times and good friends," she said in the post.

Panettiere was one of two children born to Skip Panettiere, a former New York City fire captain, and Lesley Vogel, a former soap opera star who had been the prime force behind her early career, before the two became estranged.

Panettiere began acting in commercials and soap operas, including as the ever-troubled Lizzie Spaulding on Guiding Light. In This Is Me, she wrote that the traumas her character endured, from being kidnapped to killing her mother's boyfriend, led her to associate "catastrophe with adoration."

"Grown-ups gave me positive attention when — as an actor — I failed, got sick, screamed and cried, killed, grieved, and suffered," she wrote. "Is it any wonder why I've faced so many real struggles in my life? I've often wondered whether — unintentionally — I've brought on my traumas because I'm wired to think they're good for me."

She had much warmer memories of her role as a cheerleader with supernatural powers in Heroes, which propelled her to fame in 2006. The series revolved around the mantra "Save the cheerleader, save the world."

In a statement to CBC News, show creator Tim Kring said, "Hayden was an extraordinary talent.  We were all in awe of her.  You dream of writing for an actress like her. 

"Although only 16-years-old when we cast her, she could somehow naturally hone in on the most nuanced drama, humour and pathos of any scene she was in.  But most importantly, she was a kind and gentle person who was always joy and an inspiration to work with. "

She went on to win three Teen Choice Awards for that role and was a Grammy award nominee for a children's spoken word album recorded a few years after the release of the animated movie A Bug's Life.

2 Golden Globe nominations

Panettiere later played a brash country upstart opposite Connie Britton on Nashville, which aired on ABC for four seasons before being cancelled and revived on CMT. She did her own singing in the show, which scored some hits on country charts, spawned U.S. tours and earned Panettiere two supporting actress Golden Globe nominations.

She had 11 songs recorded for Nashville appear on Billboard's Hot Country Songs charts during the show's run, including two featuring Britton, who paid tribute to her former co-star on Instagram.

"Bursting with brilliance, shining so bright," Britton wrote. "I have no words for this sad song. Just heartbreak. I love you girl. Sleep easy now."

In an interview with podcaster Jay Shetty after her memoir came out in May, Panettiere talked about the custody arrangement for her 11-year-old daughter, who lives full-time with Klitschko in Ukraine. News of the 2018 decision had prompted headlines about Panettiere giving up custody of her daughter.

"I think there's been this very common misconception that I just gave up my child," she said. "That could not be farther from the truth."

Battled depression, addiction

Panettiere said Klitschko suggested their daughter live with him full-time when the child was two years old, as Panettiere struggled with mental health challenges and addiction.

She entered rehab in 2015, while filming Nashville.

"I was the one who put myself in the first treatment centre. I was drowning," she said in a 2023 interview with Women's Health magazine.

Panettiere had endured numerous family struggles and tragedy.

Her parents' marriage was strained, and eventually ended. Her younger brother, Jansen Panettiere, who was also an actor, died of a heart condition in 2023 at age 28.

Years earlier, Hayden had made the painful decision to part professionally with her mother, who throughout her childhood had "defined and driven her" and watched her "struggle, learn, grow, fall apart, and triumph."

"She and I spent so much time together, so deeply enmeshed in each other's lives, that we started grating on each other," Panettiere wrote in her memoir. "I hated when Mom whispered about other actors during auditions, positive that they could hear her compare them to me. I hated when Mom went to industry parties and got tipsy on the merlot she loved."

In recent years, she had been in a tumultuous relationship with actor Brian Hickerson.

On Shetty's podcast, Panettiere recalled the explosion of her fame when she was cast on Heroes, including the first time she was tracked by the paparazzi. When she'd imagined the moment as a younger actress, she'd planned to look chic.

Instead, she said, "it was just sheer terror."

Panettiere also appeared in two of the Scream movies, starred as the title character in the 2009 film I Love You Beth Cooper and played the young daughter of a football coach in Remember the Titans.

WATCH | Heroes, Nashville star Hayden Panettiere dead at 36:

In her memoir, Panettiere described herself as an "optimist to the core" who refused to be defined by tragedy.

"One thing I know from my 36 years in the public eye is this: Life is a process that evolves day by day, year by year and — like it or not — you are engaged in a cycle of growth until the moment you take your last breath."

Remembering a star

News of Panettiere's death prompted a wave of tributes.

"I wish the world had more time with you because I had a burning curiosity about who you were becoming. I saw this beautiful phoenix rising from the ashes," said Viola Davis. "Rest well, Hayden."

"Oh my god — heartbroken," said talk show host and comedian Rosie O'Donnell in an Instagram post.

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Shetty, who interviewed Panettiere on his podcast just months ago, said in an Instagram comment, "I was so moved by the conversation we shared earlier this year. My love and condolences to her family and fans."