wrote in an Instagram post on Saturday in honor of International SPS Awareness Day.“Trying to overcome this autoimmune disorder has been one of the hardest experiences of my life, but I remain determined to one day get back onto the stage and to live as normal of a life as possible,” she penned. “I am deeply grateful for the love and support from my kids, family, team and all of you!”The “My Heart Will Go On” crooner — who posed with her three sons René-Charles Angélil, 25, and twins Nelson and Eddy, 13 — also sent her encouragement and support to others battling the autoimmune disorder.