By Amber Goodhand - Radar Reporter
According to a police report released on Thursday by officials in New York, the 25-year-old succumbed to what appears to be an overdose of depression medication.
An autopsy listed the cause of death as unknown, with the official report pending toxicology tests.
Ginger Carter, Leslie's half-sister, stated in the report that after Leslie fell in the shower they laid her down and thought she was sleeping — but later realized she wasn't breathing.
Leslie's father, Robert Carter, then tried to revive his daughter with CPR but after several failed attempts he called 911.
Also in the report was a statement from Ginger saying that Leslie appeared depressed the day she died, and had a long history of mental illness.
Authorities found medication near Leslie used to treat anxiety, schizophrenia, bipolar disorder and a muscle relaxant.
Leslie, married husband Mike Ashton in 2008, and gave birth to the couple's only child, daughter Alyssa Jane Ashton, on April 1, 2011.
Nick released a brief statement on Wednesday saying, “Performing is cathartic to me and I am dedicating the rest of my tour to my sister since she loved to watch me perform.” He will also be appearing Friday on Good Morning America to discuss the loss of his sister.