Jordin Sparks is honoring her late sister’s memory.
The disease, which is more common in people of African descent, causes red blood cells to stick to vessel walls, blocking blood flow and preventing oxygen from reaching tissues; the lack of oxygen can damage organs and cause pain so severe it requires hospitalization.
“She fought her entire life — all 16 years, in and out of hospitals. And she was so strong,” Sparks, 28, told PEOPLE Now exclusively on Wednesday. “She just dealt with it, you know, and there was never a complaint. I’m sure she had moments where she was like, ‘Okay, this hurts,’ but she was one of the strongest people that I’ve ever encountered.”
While the singer and her family are devastated by the loss, they’ve set up a GoFundMe page to raise money for sickle cell research in honor of Bryanna, who was laid to rest Monday.
“Her dream was to raise awareness and to find a cure for it,” says Sparks. “People know about sickle cell, but they don’t know how rampant it is or how many people are affected by it. It kills 100,000 people a year, so … Why aren’t we talking about this more?”
Adds Sparks: “We’re just trying to raise as much as we can to help find a cure so nobody else has to go through this.”
Sparks suffered the loss of four loved ones in one week. Her younger cousin Q and friends Rasual Butler, a former NBA player, and his wife, American Idol alum Leah LaBelle, also died last week.
“My heart is just so heavy & broken,” Sparks wrote on Instagram last week. “I’m in shock, numb and feel everything all at the same time.”