Billie Lourd lost both her mother and grandmother last week when Carrie Fisher and Debbie Reynolds died on consecutive days, and the 24-year-old actress took to Instagram to break her silence on Monday.

“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. 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,” Lourd wrote as a caption with an image of the three generations of Hollywood entertainers.

Last week, a family spokesperson mentioned Lourd in a statement when Fisher died: “It is with a very deep sadness that Billie Lourd confirms that her beloved mother Carrie Fisher passed away at 8:55 this morning. She was loved by the world and she will be missed profoundly.”

Also Read: Carrie Fisher, Debbie Reynolds Joint Funeral Planned (Report)

Lourd had remained silent since the statement until Monday’s Instagram message. Fisher and Reynolds will be memorialized in a joint funeral and buried side-by-side at Forrest Lawn in Burbank, according to a TMZ report.

TMZ has also learned that after an autopsy was performed on Fisher, a death certificate issued on Friday does not list a cause of death because that is still not clear. The L.A. County Coroner’s Office will conduct more tests of the 60-year-old to learn what caused her heart to stop while returning to Los Angeles on a United Airlines flight on Dec. 27.

Only family and friends are invited to the Forest Lawn funeral, but arrangements will be made for a memorial for the public at a later date. Those plans are being placed on the back burner to allow Lourd time to mourn.

Also Read: HBO Moves Up Release of Carrie Fisher, Debbie Reynolds Doc 'Bright Lights'

Reynolds died following a stroke last Wednesday at the age of 84, just one day after the death of her daughter, “Star Wars” heroine Fisher.

Lourd is the third generation of actresses from the family, with a successful career of her own. Lourd had an appearance in “Star Wars: The Force Awakens” and is a star of Fox’s “Scream Queens.”