UPDATE: According to a police report, Leslie Carter suffered an apparent overdose and had been taking medication for depression, reports People.
Her stepmother, Ginger Carter, told the police that Leslie had a "long history of mental illness" and appeared depressed the morning before she died. Us Weekly reports that prescription drugs Olanzapine, and Alprazolam -- used to treat schizophrenia and bipolar disorder -- as well as Cyclobenzaprine, a muscle relaxer were found near her body.
Officials are still waiting on the results of the toxicology report to determine the official cause of death.
PREVIOUSLY: The autopsy performed on Leslie Carter didn't offer any answers as to why the 25-year-old sister of Backstreet Boy Nick Carter and one-time pop star Aaron Carter died suddenly on Tuesday.
The Chautauqua County Coroner's Office confirmed to E! News that the autopsy was inconclusive, presenting with no visible signs of trauma.
"We are awaiting a toxicology report to determine the cause of death," said coroner Richard Mackowiak. "The body has been released to the family. Results of the toxicology test are made public at the discretion of the family."
Results could take up to six weeks to come back, but there is already speculation that drugs played a role in Leslie's death. TMZ reported yesterday that Leslie was battling an addiction to prescription medication before her death. Sources claim Carter had moved from Canada to upstate New York to try to kick her addiction to Xanax and other prescription medications.
TMZ's sources say family members believed Leslie would be OK to stay home alone for about an hour on Tuesday while they ran errands, but when they returned they found her unconscious.
Like her brothers, Leslie also tried her hand at a music career. According to MTV News, she recorded a never-released debut album under the Dreamworks label in 1999. In 2001, her song "Like Wow!" appeared on the soundtrack for the movie "Shrek," and despite other attempts she might best be remembered for her family's reality show "House of Carters," which aired for one season in 2006.
Check out photos of the Carter siblings below: