Carrie Fisher, Billie Lourd
Billie Lourd and Carrie Fisher attend the Premiere of Walt Disney Pictures and Lucasfilms’ “Star Wars: The Force Awakens” on Dec. 14, 2015 in Hollywood, California. Getty Images/Jason Merritt

Billie Lourd recently paid tribute to her late mom, Carrie Fisher, on her birthday.

On her Instagram account, the “Scream Queens” actress uploaded a throwback snap of her and her mom wearing matching night gowns. Fisher’s right hand is carefully placed on her waist, while her left hand was positioned on top of Lourd’s shoulder. Both Fisher and Lourd have smile on their faces.

Lourd captioned the photo with a simple “Happy Birthday Mom” greeting and used several emojis.

Last month, Lourd spoke with Ellen DeGeneres on the “Ellen Show” about her struggles with living life without her mom and grandmother, Debbie Reynolds. Fisher and Reynolds died one day apart. “It’s completely surreal. There’s no way to really explain it – it’s so hard to talk about,” she said.

The actress admitted that she’s been having mixed emotions about the recent events in her life. “If I say I’m doing good, I’m too happy. If I say I’m not doing good, then I’m a mess. So it’s really hard to know what to say about it because it’s so surreal and impossible to deal with,” she explained.

Fisher passed away on Dec. 27, 2016, four days after she suffered a medical emergency and was rushed to a hospital. Days later, the coroner listed her cause of death as cardiac arrest. Reynolds passed away on Dec. 28.

But in June, a report from the Los Angeles County coroner’s office confirmed that Fisher had cocaine, heroin and ecstasy in her system when she became ill during her flight from London to Los Angeles. It was also revealed that the “Star Wars” actress died from sleep apnea.

Following the reports, Lourd released a statement to People acknowledging the fact that her mom battled drug addiction and mental illness all her life.

“She ultimately died of it. She was purposely open in all of her work about the social stigmas surrounding these diseases. She talked about the shame that torments people and their families confronted by these diseases. I know my mom, she’s want her death to encourage people to be open about their struggles,” she said.