The actress, best known as Star Wars‘ Princess Leia Organa, suffered a heart attack at the end of last year. She was flying from London to Los Angeles on Friday, Dec. 23, when she went into cardiac arrest. Paramedics removed her from the flight and rushed her to a nearby hospital, where she was treated for a heart attack. She later died in the hospital, just one day before her mother, Debbie Reynolds, passed away.
Lourd, 24, took to Instagram to pay tribute to her mother and grandmother days after their deaths.
“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 Jan. 2, her first time commenting on their deaths. “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.”
Fisher had long been open about her struggle with bipolar disorder and substance abuse issues, starting at only age 13 when she began smoking marijuana.
She said she later dabbled in drugs like cocaine and LSD.
Fisher explored her issues with addiction in her 1987 bestselling, semi-autobiographical novel, Postcards from the Edge, which was later turned into a movie starring Meryl Streep.
“I couldn’t stop, or stay stopped. It was never my fantasy to have a drug problem,” she told WHO in 1987. “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.”
She told WHO in 2013, “The only lesson for me, or anybody, is that you have to get help. I’m not embarrassed.”
To seek support for anyone suffering from mental illness, contact the Lifeline.
This story originally appeared on PEOPLE.com.