"'If my life weren't funny then it would just be true and this is unacceptable,'" the Scream Queens star wrote, quoting her mom in the caption for a sweet throwback pic with the Star Wars actress.
"Finding the funny might take a while," Lourd, 24, continued, "but I learned from the best and her voice will forever be in my head and in my heart."
Fisher died on December 27 at the age of 60, days after suffering a massive heart attack during a flight from London to Los Angeles. Fisher's mother, screen legend Debbie Reynolds, died the following day after she had a stroke at her son Todd Fisher's home in Beverly Hills. She was 84.
Singin' in the Rain star Reynolds was laid to rest with some of her daughter's ashes at Forest Lawn Memorial Park in L.A. on January 6, a day after Fisher's life was celebrated by her A-list friends at the Postcards From the Edge writer's Beverly Hills home.
Lourd, who is Fisher's only child, broke her silence on January 2 after their sudden deaths, taking to Instagram in an emotional post to thank fans for their well wishes.
"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," she captioned a photo of herself as a young girl with her mom and grandmother. "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."
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