Billie Lourd breaks silence on deaths of mom Carrie Fisher and grandmother Debbie Reynolds

Carrie Fisher and Debbie Reynolds were known as entertainment icons to millions around the world, but they were known as "mom" and "grandma" to 24-year-old actress Billie Lourd.

Lourd broke her silence on the news on Monday, sharing an old photo of herself, Fisher, and Reynolds on Instagram. With it, she wrote, "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 own and only Momby. Your love and support means the world to me."

Fisher's death was confirmed last Tuesday morning by way of the family's spokesperson, saying: "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."

Other than that statement, Lourd remained silent on social media and had not commented on the heartbreaking deaths of her mother, Fisher, and grandmother, Reynolds, up until now.

Fisher died Tuesday morning after suffering a what was described as a massive heart attack on Friday while in flight to Los Angeles from London, where she was filming the series "Catastrophe" on which she had a recurring role. She was rushed from LAX airport to the UCLA Medical Center Friday afternoon when the plane landed. Just one day later, Reynolds, 84, was rushed to Cedar-Sinai in L.A. for a reported stroke. She died just hours after she was transported to the hospital. Her son, Todd Fisher, told Variety, "She wanted to be with Carrie."

Lourd — who is the daughter of Fisher and CAA veteran Bryan Lourd, who was with the "Star Wars" actress from 1991 to 1994 — stars on Fox's "Scream Queens." In the series, her character wears fuzzy earmuffs, which she told Variety were a tribute to her mother's iconic Princess Leia buns.

In the past days since Fisher's death, Lourd's "Scream Queens" co-stars have shown their support with various social media messages, including those from Lea Michele, Jamie Lee Curtis, Ariana Grande, Taylor Lautner and John Stamos.

Lourd, her mother and grandmother were last together at a public event in 2015 at the SAG Awards where Reynolds was honored with the Lifetime Achievement Award (pictured).