Céline Dion Says Sons Fuel Her to Fight Stiff-Person Syndrome (Exclusive)

As she navigated grief and severe health struggles over the years, Céline Dion moved fans around the world with her unrelenting courage and resilience.

On her most difficult days, the music superstar — who was diagnosed with the rare autoimmune and neurological disorder stiff-person syndrome in August 2022 nearly six years after her husband, René Angélil, died from throat cancer — tells PEOPLE exclusively in its latest cover story (on stands Friday, June 14) that she finds strength in, and for, her three sons.

While Dion, who’s mom to René-Charles, 23, and 13-year-old twins Nelson and Eddy, had been battling mysterious health struggles beginning in the mid-2000s, her symptoms (including excruciating muscle spasms, difficulty walking and breathing) dramatically worsened in the years ahead of her SPS diagnosis.

“I barely could walk at one point, and I was missing very much living. My kids started to notice. I was like, ‘Okay, they already lost a parent. I don’t want them to be scared,'” says Dion, 56, who lifts the veil on her journey in a Prime Video documentary, I Am: Celine Dion (streaming globally June 25), directed by Academy Award-nominated director Irene Taylor. “I let them know, ‘You lost your dad, [but] mom has a condition and it’s different. I’m not going to die. It’s something that I’m going to learn to live with.”

For more on Céline Dion’s fight back to the stage and her life now with her three sons, pick up the latest issue of PEOPLE, on newsstands Friday, June 14.

After canceling a planned Las Vegas residency and tour dates in late 2021 and 2022, Dion announced in a tearful video on Instagram in December 2022 that she had been diagnosed with the incurable illness.

“I’ve been dealing with problems with my health for a long time, and it’s been really difficult for me to face these challenges and to talk about everything that I’ve been going through,” she told fans, acknowledging that she was still learning about the condition and its impact on her life and career.

In the upcoming film’s powerful trailer, the five-time Grammy winner emphasizes how hard she’s been working to get back to the stage.

“I miss it so much. The people, I miss them,” says Dion, who received a standing ovation at the Grammys in February when she made a surprise appearance to present Taylor Swift the Album of the Year award, which the “My Heart Will Go On” singer first won 27 years ago. “If I can’t run, I’ll walk. If I can’t walk, I’ll crawl … I won’t stop.”

Dion will also be opening up about her health battle in a sit-down interview with Hoda Kotb for an NBC News primetime special, airing Tuesday, June 11 at 10 p.m. EST.

“I did not take the time — I should have stopped, take the time to figure it out,” she told Kotb (in a preview that aired on Today). “My husband as well was fighting for his own life. I had to raise my kids, I had to hide. I had to try to be a hero.”