Celine Dion Has Lost Control of Her Muscles: Sister

Amid her ongoing struggle with the rare neurological condition known as stiff-person syndrome, Celine Dion has reportedly lost muscle control, the singer's sister says. "She works hard, but she doesn't have control over her muscles," Claudette told a French media outlet, as translated and reported by E! Online and Us magazine. "What breaks my heart is that she's always been disciplined. She's always worked hard. Our mother always told her, 'You're going to do it well, you're going to do it properly.' 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."

Dion, 55, was forced to cancel her world tour earlier this year due to her medical battle. The disorder can cause muscle spasms, pain, and stiffness. Her sister says another sister has been living with Dion in Las Vegas while experts on the syndrome treat her. "The vocal cords are muscles, and the heart is also a muscle," Dion's sister continued in her interview. "This is what [gets to] me. Since it's one case in millions, scientists didn't do that much research, because it didn't affect that many people." Dion first revealed the diagnosis last December. (More Celine Dion stories.)