Why Celine Dion's voice might sound different on new single

After an emotional video posted on Instagram explaining her stiff person syndrome diagnosis, Celine Dion releases a new song proving to fans the disease will not stand in her way.

"The sun will rise again, the storms subside again, this is not the end," Celine Dion sings in her new single "Love Again."

The Quebec-born artist is making a comeback with a ballad for an upcoming movie, also titled "Love Again," which she co-stars in.

The single "Love Again" is one of five songs sung by Dion set to appear in the film, and marks the first time the singer has released music since her stiff person syndrome diagnosis (SPS) last year, a rare neurological condition with no cure.

The film, out this May, follows the story of a grieving fiancé falling in love after losing her partner. Dion plays a matchmaker helping the two main characters come together.

In an emotional video posted to Instagram Dec. 8, Dion explained to fans why she needed to postpone her world tour and how difficult it is for her to sing the way she used to.

SPS is a neurological condition that impacts a person's muscles, and in Dion’s case, it hinders her ability to perform.

People with SPS have described the condition as "excruciating" and say it causes "debilitating" pain because of heightened sensitivity to noise and touch. The U.S. National Institute of Neurological Disorders and Stroke says SPS has "features" of an autoimmune disorder.