For Billie Lourd, the festive season was a difficult one. In the space of just two days, she lost both her mother, Carrie Fisher, and her grandmother Debbie Reynolds.

In a post on Instagram on Monday, the 24-year-old star of Scream Queens broke her silence with a message to everyone who has offered her support since her family’s double heartbreak.

“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, under a photo of herself as a child with her mum and grandma.

“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 died aged 60 on 27 December, after going into cardiac arrest while on a flight from London to Los Angeles. Lourd, who is Fisher’s only child, released a statement confirming her mother’s death last Tuesday morning, but until now had not otherwise commented publicly on her mother and grandmother’s deaths.

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“It is with a very deep sadness that Billie Lourd confirms that her beloved mother Carrie Fisher passed away at 8:55 this morning,” said Lourd’s spokesman at the time. “She was loved by the world and she will be missed profoundly.”

Lourd’s tribute to her mother and grandmother came on the same day that Fisher’s Star Wars co-star Mark Hamill penned a moving essay about his old friend. In the piece, published by The Hollywood Reporter on Monday, Hamill revealed how Fisher won him over the first time they met, before they began working on the first Star Wars movie.

“She was 19 years old at the time. I was a worldly 24,” Hamill wrote. “So I was thinking, ‘Oh my God, it’ll be like working with a high school kid’.”

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But Fisher’s famous quick wit meant that Hamill quickly understood he’d been mistaken. “I was just bowled over,” he said. “I mean, she was just so instantly ingratiating and funny and outspoken. She had a way of just being so brutally candid. I’d just met her but it was like talking to a person you’d known for 10 years.”

He added: “She just sucked you into her world… She was so committed to joy and fun and embracing life.”

Debbie Reynolds, the 84-year-old star of iconic Old Hollywood movies including Singin’ in the Rain, It Started With a Kiss and How the West was Won, died the day after her daughter, after suffering a stroke in Los Angeles.

Reynolds’ son and Fisher’s brother, Todd Fisher, told Variety that his mother “wanted to be with Carrie”. In an interview with ABC News, he said that his family was planning a joint funeral for the two legendary actresses.

Images: Rex Features