Legendary Canadian singer Celine Dion no longer has ‘control over her muscles,’ according to her older sister Claudette.

A year after the My Heart Will Go On hitmaker was forced to cancel her world tour last December, her sibling, 74, suggested that it may be awhile before Celine, 55, returns to the stage following her battle with a neurological disorder called stiff person syndrome.

Celine’s condition, which is progressive and incurable, causes the body to attack its own nerve cells and severely impacts mobility.

‘She’s working hard, but she doesn’t have control over her muscles. What breaks my heart is that she’s always been disciplined,’ Claudette told 7 Jours. She’s always worked hard. Our mother always told her, ‘You’re going to do it well, you’re going to do it properly.’

She continued: ‘It’s true that in both our dreams and hers, the goal is to return to the stage. In what capacity? I don’t know.’

Health battle: Legendary Canadian singer Celine Dion no longer has ‘control over her muscles,’ according to her sister Claudette; seen in 2019

While research is ongoing into the condition, the rarity of it means progress has been slow.

Claudette added: ‘The vocal cords are muscles, and the heart is also a muscle. This is what comes to get me. Because it’s 1 out of a million case, the scientists haven’t done that much research because it didn’t affect that many people.’

Celine’s family charity, Fondation Maman Dion, has been inundated with messages of support for the star.

Claudette said: ‘Some people have lost hope because it’s all illness that isn’t well known. If only you knew the number of phone calls the Foundation gets about Celine! People tell us they love her and they’re praying for her. She gets so many messages, presents and blessed crucifixes.’

Claudette has previously revealed that despite working with ‘the top researchers in the field’, her sister has seen little improvement in her health.

She told Le Journal de Montreal: ‘We can’t find any medicine that works, but having hope is important.’

In October, Claudette said Celine was not yet reliant on a wheelchair to get around and still planning to return to performing.

An icon: A year after the My Heart Will Go On hitmaker was forced to cancel her world tour last December, her sibling, 74, suggested that it may be awhile before Celine, 55, returns to the stage following her battle with a neurological disorder called stiff person syndrome (pictured in 2012)

Celine’s condition, which is progressive and incurable, causes the body to attack its own nerve cells and severely impacts mobility; seen in 2019

People who suffer from stiff person syndrome (SPS) can turn sufferers into ‘human statues,’ leaving them struggling to walk or talk.

The condition, which is thought to affect just one in a million people, can also lead to spasms that generate enough force to fracture bone.

Usually, patients are diagnosed around ages 30-50, and they are mostly women.

The star first revealed her diagnosis in December 2022 via a teary Instagram post, and months later canceled her world tour, which was scheduled to begin at the end of 2023.

In September, a video surfaced on YouTube entitled ‘Celine Dion’s Family Reveals How She Is Dying’, in which an unidentified narrator says that her incurable disease is ‘progressing very quickly’. The video has since been republished on TikTok, where it received more than 430,000 views.

The clip triggered rumors on social media that the Grammy award-winning artist is now wheelchair-bound and struggling to move.

Celine’s sister, however, denied this is the case.

‘I know that morally, mentally, she is strong. She is not depressed at all … she really has the joy of living. We will get through this,’ her sister, Claudette, told the French-language site showbizz.net.

As for the rumors, Claudette said: ‘Why do they say she is in a wheelchair? Why do they say she had cancer? Why are you inventing?

Despite Celine Dion’s pain, she’s not given up on plans to return to the stage, according to her sister.

Earlier this year, Claudette also told showbizz.net that the icon is recuperating in Denver and following her doctors’ care plan closely because she ‘wants to come back, that’s for sure.’