Wladimir Klitschko mourns Hayden Panettiere after her death

Wladimir Klitschko said his family is in “profound shock and grief” after the death of his former fiancée, actor Hayden Panettiere, who died Sunday in Greenville, South Carolina, at 36.

The former world heavyweight boxing champion, who shares an 11-year-old daughter, Kaya, with Panettiere, posted an emotional tribute on Instagram, calling her an important part of his life even after their relationship ended.

“The announcement of Hayden’s tragic death saddens me deeply. She left this world far too soon,” Klitschko wrote. “Hayden was, although no longer my partner, an important part of my life and the mother of our daughter, Kaya.”

Klitschko, a Ukrainian boxer and brother of Kyiv’s mayor, shared a photo of Kaya sitting on her mother’s shoulders. He praised Panettiere’s “incredible career through immense talent” and said she had also faced “the darker sides of a very demanding industry.”

“Nothing will erase the times we shared or the place she had in our lives,” he wrote. “To our daughter Kaya, I will always speak of her mother with respect and make sure she remembers the person she was.”

He also offered condolences to Panettiere’s parents, friends and fans, and asked that the family’s privacy be respected. “Young and talented people like Hayden should not leave this world so soon,” he wrote. “Rest easy, Hayden. May you find eternal peace.”

The Greenville County Coroner’s Office said the cause of death is pending further investigation. An autopsy was completed Monday and found “no signs of trauma” that would have contributed to her death. Police said the preliminary investigation found no signs of foul play or suspicious circumstances, and that an acquaintance placed the 911 call.

The BBC reported that audio from police dispatchers and crews said responders were called for a “cardiac arrest” and described efforts to resuscitate a woman after a possible “overdose.” The coroner’s office said crews treated a woman in “cardiac arrest,” the BBC reported, but officials have not confirmed a cause of death.

Panettiere was best known for her roles in the television series “Heroes” and “Nashville.” Before those roles, she worked as a child actor, appearing in projects including “Remember the Titans,” “Raising Helen” and the soap opera “Guiding Light.” Her final big-screen appearance came earlier this year in the movie “Sleepwalker,” according to the BBC.

Tributes have continued from former colleagues. Connie Britton, Panettiere’s co-star on “Nashville,” wrote on Instagram, “This was Hayden. Bursting with brilliance, shining so bright.” She added, “I have no words for this sad song. Just heartbreak. I love you girl. Sleep easy now.”

Masi Oka, who appeared with Panettiere on “Heroes,” wrote on X that he was “absolutely heartbroken,” remembering her “beautiful spirit, immense talent, and the joyful energy she brought to everything she did and the people around her.” Beth Chamberlin, who played her on-screen mother on “Guiding Light,” called her “the most brilliant child actor I’ve ever seen.”

Panettiere had spoken publicly about postpartum depression and addiction. In her memoir, “This Is Me: A Reckoning,” published earlier this year, she described reluctantly signing over custody of Kaya to Klitschko when their daughter was nearly 3. She wrote that being apart from her daughter was “the most gut-wrenching experience of my life.”

Klitschko and Panettiere announced their engagement in 2013 and welcomed Kaya in 2014. They were no longer engaged by 2018. Panettiere later said in interviews that she had developed a good co-parenting relationship with Klitschko, visited her daughter in Ukraine and spoke with her regularly on FaceTime.

“I will always want her here. I always miss her,” Panettiere said of Kaya in a May interview on the “Jay Shetty Podcast.” “I always want to have my arms wrapped around her, but that’s just not the way life is right at this moment.”