Billie Lourd Weighs In On Carrie Fisher’s New Autopsy Report

06/20/2017 05:37 pm EDT

Billie Lourd is speaking out about her late mother Carrie Fisher's toxicology report. The Los Angeles County Coroner's Office confirmed that the iconic Star Wars actress died of sleep apnea, and had heroin and cocaine in her system at the time of her death. According to 24-year-old Billie Lourd, another factor that contributed to her mother's passing was "mental illness."

In a statement given to People magazine, the Scream Queens actress addressed the coroner's report.

Up Next: Carrie Fisher's Brother 'Not Shocked' About Drugs Found In Her System When She Died

"My mom battled drug addiction and mental illness her entire life. She ultimately died of it," Lourd said. "She was purposefully open in all of her work about the social stigmas surrounding these diseases."

She continued by saying: "She talked about the shame that torments people and their families confronted by these diseases. I know my Mom, she'd want her death to encourage people to be open about their struggles. Seek help, fight for government funding for mental health programs. Shame and those social stigmas are the enemies of progress to solutions and ultimately a cure. Love you Momby."

On December 23, Carrie Fisher died after going into cardiac arrest while on a flight from London to Los Angeles. On the following day, Carrie's mother, Singin' In The Rain star Debbie Reynolds, passed away.

In the days after the death of her mother and grandmother, Lourd took to Instagram to pen an emotional tribute to her late family members.

More: Carrie Fisher Had Heroin and Cocaine In Her System When She Died, Report Says

"Receiving all of your prayers and kind words over the past week has given me strength during a time I thought strength could not exist," Lourd wrote on Instagram on Jan. 2. "There are no words to express how much I will miss my Abadaba and my one and only Momby. Your love and support means the world to me."

Carrie Fisher was open about her struggles with bipolar disorder and substance abuse. In her 1987 best-selling, semi-autobiographical novel, Postcards from the Edge, Fisher detailed her addiction issues.

"I couldn't stop, or stay stopped. It was never my fantasy to have a drug problem," she said during an interview with People back at the time the book was released. "I'd say, 'Oh, f— it, I haven't done anything for a couple of months, why not? Let's celebrate not doing them by doing them.' I got into trouble each time. I hated myself. I just beat myself up. It was very painful."

Photo Credit: Getty Jamie McCarthy

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