Hayden Panettiere Allegedly Overdosed and Secretly Entered Rehab Weeks Before Her Fentanyl-Related Death

Hayden Panettiere allegedly overdosed before secretly entering a Malibu rehab facility just weeks before her death from an accidental fentanyl overdose.

Newly released details from the Greenville County Coroner's Office report shed light on the actress' final weeks and her long history of addiction.

Either Brian or Zach Hickerson — the name was redacted — told investigators that Hayden had "a long history of drug, alcohol, and nitrous oxide abuse" and that he "has had to administer Narcan to the decedent before," per Page Six.

One of the brothers also said Hayden "was in a drug rehab facility in Malibu, California, up until a few weeks ago."

Her father, Skip Panettiere, confirmed that Hayden "had recently been released [from] rehab" in Malibu.

He said she spent "two or three weeks" at the facility.

Skip also said Hayden "struggled with addiction since her early 20s and [had] been in multiple rehab facilities since that time."

Skip also discussed his daughter's struggles following the birth of her daughter, Kaya, 11.

He said Hayden "suffered from postpartum depression after the birth of her daughter," adding that her "addiction issues... escalated since then."

The Heroes actress previously opened up about her postpartum depression.

"I wish somebody told me that that was a possibility, told me it's OK if you birth your child and you're not immediately like, 'Oh my god, I love you more than anything in the entire world!'" she told E! News. "I just thought there was something seriously wrong with me, so I thought, 'Fireball will fix this — duh!' And it didn't. It does for a moment, but then it makes everything worse."

The newly released report also detailed what investigators discovered inside the Airbnb in Greenville, South Carolina, where Hayden died on August 16 at 36.

Investigators found "a small clear plastic bag of a white powdery substance in a suitcase belonging to the decedent inside of a gray sunglasses case."

They also discovered "a cut straw with residue... inside of a small blue-colored makeup-type bag... inside [a] black bookbag/purse belonging to the decedent."

An Adderall bottle found on the kitchen table contained "a small clear plastic bag with blue-colored tablets that appeared to possibly be pressed pills and a cut straw."

The pills and straws later tested positive for fentanyl.

Investigators also found "multiple prescription bottles on the kitchen table and a small teal blue-colored lunchbox with glass vials [as well as] prefilled and empty syringes located in the refrigerator."

The coroner determined that Hayden's death was an accident on September 22.

Her death was caused by "the toxic effects of fentanyl, 4-ANPP, Alprazolam, Methocarbamol, and Quetiapine."