The 55-year-old was diagnosed with Stiff Person Syndrome in December – a rare and incurable neurological disease that can cause debilitating muscle spasms – and her presence at the screening, held at AMC Lincoln Square in New York City, was clearly missed by her co-stars, Priyanka Chopra and Sam Heughan.
Both stars spoke fondly of Celine and shared their support for her during her continued health struggles, with Priyanka telling People: "She's gracious. She's funny. She didn't need to, but she gave us so much of her time. She's just a wonderful, wonderful person."
She added. "I wish her so much love and luck, and I know she wanted to be here, but I'm just so happy she's part of this movie. She's such an integral part of it."
Sam also spoke of his "admiration" for Celine, saying: "I mean, come on, you're working with Celine Dion. She's not only a cultural icon, a music icon, [but] she's really good and she's really funny.
"The same goes for Priyanka. [She has] such a great heart, she's the heart of the movie, I think. And I've got so much admiration for both of these brilliant women who are at the top of their game."
When asked if he gave Celine any advice for her acting debut, Sam replied: "I don't think she needs any help. She's brilliant at what she does. She's so funny. She's playing herself in the movie, she's got her own love story of her own in real life. It was so touching to work with her."
Not only is Celine starring in the film, but she has also provided music for the soundtrack, including her new single 'Love Again' which is her first new original material in nearly four years.
The song is her first since 2019's 'Courage' off the album of the same name, following which she retreated from the spotlight due to the pandemic and health troubles of her own.
After canceling shows due to "persistent muscle spasms," she revealed that she had been diagnosed with Stiff Person Syndrome and would stay home to recover. She said at the time that the spasms caused by her illness have impacted her everyday life.
She explained: "They sometimes cause difficulties when I walk, and it's not allowing me to use my vocal cords to sing the way I am used to.
"I have a great team of doctors working alongside me to help me get better and I'm working hard with my sports medicine therapist every day to build back my strength and my ability to perform again but I have to admit it's been a struggle."
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