Hayden Panettiere‘s death continues to be investigated, casting a somber shadow over what would have been her 37th birthday, Friday, Aug. 21.

The shocking death of the actress – best known for roles in “Nashville,” “Heroes,” “Ice Princess,” and “Bring It On” – has spawned endless tributes after she was found unresponsive at Judson Mill Lofts, an apartment complex in Greenville, South Carolina, local police told USA TODAY.

A 911 call obtained by Reuters, TMZ and other outlets revealed the “Scream” franchise actress was in cardiac arrest after a possible overdose.

Brian Hickerson, her on-and-off boyfriend, has been at the center of questions surrounding Panettiere’s death after police confirmed he was with her when she died. The pair’s tumultuous relationship was marked by abuse allegations and a jail stint for Hickerson.

As Hickerson and her loved ones speak out, here’s what we know so far as the investigation continues.

Brian Hickerson’s brother speaks out on Hayden Panettiere death

Zach Hickerson, brother of Panettiere’s on-again, off-again boyfriend Brian Hickerson, shared his account of the circumstances surrounding the actress’s death in an interview with TMZ published Aug. 21.

Hickerson said he and Brian discovered Panettiere unconscious after he visited the pair at their Airbnb in Greenville. Upon seeing Panettiere’s condition, Hickerson said his brother administered Narcan, a medication that can rapidly reverse an opioid overdose, to the actress. He said the two men later attempted CPR until authorities arrived.

“There are a lot of assumptions, speculations and accusations currently swirling,” Hickerson told the outlet. “The truth will come out as the authorities complete and release additional details from the investigation. And that is important because the people who loved and adored Hayden deserve the truth.”

Hickerson said he is “beyond heartbroken and devastated” by Panettiere’s death, adding, “Hayden was one of my dearest and closest friends that I loved and cared about for the last 8 years.”

Hayden Panettiere’s ex Wladimir Klitschko honors late star on her birthday

Panettiere’s ex-fiancé, Ukrainian boxer Wladimir Klitschko, paid tribute to the late actress on her birthday.

“Instead of celebrating the way we had planned, today we celebrate her life, her spirit, and the love she brought into this world,” Klitschko captioned a photo of Panettiere. “I want to thank all of Hayden’s fans, friends, and everyone who has reached out for the incredible outpouring of love and support. At a time filled with so much sadness, your kindness has reminded me that there is still so much good in humanity.”

The athlete then made a heartfelt call.

“If you’re reading this, I ask just one thing: even if only for a moment, think about LOVE. Reach out to a friend. Forgive someone. Be kind,” he said. “Love is a superpower. Use it.”

He added, “Happy Birthday, Hayden. You are loved, you are missed, and you will never be forgotten.”

The pair were on-and-off for a decade, and got engaged in 2013. Panettiere gave birth to their daughter, Kaya, in 2014, but gave up custody to Klitschko in 2018, following her battle with postpartum depression and addiction. The 11-year-old now lives in Ukraine with Klitschko.

Neutrogena response to Hayden Panettiere’s death

Neutrogena shared its first statement reacting to Panettiere’s death after it faced backlash in recent days over resurfaced comments from the actress, who previously claimed the cosmetics company attempted to end a partnership with her after she spoke out about postpartum depression.

In a statement posted on its Instagram account, Neutrogena said it was “deeply saddened by” Panettiere’s death.

“For more than a decade, Hayden was a valued member of our Neutrogena community,” the statement read. “We are proud to have partnered with her and understand that we made her feel unsupported during a very difficult time. This is not what Neutrogena stands for or who we want to be.”

The company continued by applauding Panettiere’s “courage in sharing her challenges” and saying that it is making a “significant investment to a long-standing community health partner to help give more women access to the support they need, including care for postpartum depression.” Neutrogena said it will share further details at a later date.

In her 2026 memoir “This Is Me: A Reckoning” and interviews promoting the book, Panettiere alleged Neutrogena wanted to cancel a long-standing contract with her after she spoke publicly about suffering from postpartum depression. She said on the “On Purpose with Jay Shetty” podcast that the company claimed she had violated their “morals clause.”

“When I got that call that Neutrogena wanted to fire me over that, and my representative at the time said, ‘That’s illegal. You can’t do that.’ And even though she saved the day, that year, I knew that that was going to be it. I was not going to be invited back the next year,” she said.

Hayden Panettiere ex Brian Hickerson breaks silence on actress’ death

Panettiere’s on-again, off-again boyfriend, Brian Hickerson, released his first statement addressing the actress’ death on Aug. 20 via his attorney, Sloan Ellis, according to TMZ.

In the statement, Hickerson reiterated Greenville, South Carolina police’s statement that there were “no signs of foul play” and added, “Out of respect for Hayden’s loved ones and the ongoing investigation, there will be no further comment at this time.”

Hayden Panettiere’s mother, Lesley Vogel, addresses estranged relationship, boyfriend Brian Hickerson

Lesley Vogel, Panettiere’s estranged mom, continues to speak out amid her death.

Her initial remarks following the actress’ death, about “young people who grow up in the entertainment industry” and “find the wrong path,” sparked a media backlash, with some suggesting Vogel’s remarks were an indicator of their strained relationship. But her former manager blamed their distance on Hickerson.

“Although my daughter and I were estranged, it was not for lack of care or love. It was due to the involvement of a toxic individual who I believe led to her death,” Vogel told Entertainment Tonight in a statement released Aug. 20. Panettiere’s mother did not name the individual, although her remarks echo previous comments she made about Hickerson.

“This person in her life that we have been trying to get rid of for quite some time was with her at her death, and that was Brian Hickerson,” Vogel told NBC News in a phone interview Aug. 18.

Hayden Panettiere cause of death: Actress was in cardiac arrest

A cause of death for Panettiere has not yet been confirmed.

Medical assistance was administered to Panettiere upon authorities’ arrival, but the actress was later pronounced dead, according to police, who added that no foul play is suspected. The actress allegedly went into cardiac arrest after a possible overdose, according to a 911 call obtained by Reuters, TMZ and other outlets.

Hayden Panettiere toxicology report

An official autopsy or toxicology report on Panettiere’s death has not been released.

The results of these reports could take up to three months to complete, the Greenville County Coroner’s Office previously confirmed to USA TODAY.

Hayden Panettiere funeral

A public memorial service for Panettiere has not yet taken place.

Panettiere’s mother, Lesley Vogel, previously confirmed to NBC News that the actress’s body has been returned to the family.

Vogel told the outlet that funeral plans are currently being worked on.

Contributing: KiMi Robinson, Sameen Chaudhry and Anthony Robledo, USA TODAY