"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 Monday. "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."
VIDEO: Carrie Fisher and Debbie Reynold's Intimate Bond Takes Spotlight in HBO Documentary Bright Lights
The 24-year-old Scream Queens star captioned a throwback photo that showed her sticking out her tongue as a child, as she places her head on Reynolds's shoulder. Fisher stands behind her, leaning down and flashing a smile at the camera.
Following Reynolds's death, her son, Todd Fisher told Variety his mother "wanted to be with Carrie", adding that her passing was too heartbreaking for the iconic actress.
We're keeping Billie in our thoughts during this difficult time.