Celine Dion鈥檚 sister says the Grammy Award-winning singer doesn鈥檛 have control of her muscles as she continues to live with a rare neurological disorder.

Claudette Dion says in a new French-language interview that her sister is working hard to overcome her illness, called 鈥渟tiff person syndrome.鈥�

She tells 鈥�7 Jours鈥� that the illness affecting an estimated one in a million people is not yet well understood by current medical science, noting that vocal cords are muscles too.

The 75-year-old says the Fondation Maman Dion, where she is CEO and spokesperson, receives numerous messages asking about Celine Dion鈥檚 health and well-being.

Claudette Dion says she hopes her sister can return to the stage one day, but isn鈥檛 certain when that could happen.

The Quebec-born songstress announced her diagnosis in December 2022 after experiencing sudden severe muscle spasms.

Earlier this year, she cancelled all her scheduled tour dates through April 2024 and apologized to her fans in a social media post.

鈥淯nfortunately, the spasms affect every aspect of my daily life, sometimes causing difficulties when I walk and not allowing me to use my vocal cords to sing the way I鈥檓 used to,鈥� Celine Dion wrote at the time.

Stiff person syndrome causes rigid muscles and painful muscle spasms, which can be triggered by such things as loud noises or light touch. The cause isn鈥檛 known, but it is thought to be an autoimmune disorder.

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