Rihanna Helps 5-Year-Old Fan Look for Bone Marrow Donor

Rihanna is stepping forward to help a 5-year-old New York City girl find a bone marrow donor – the second time in a year that the Grammy Award winner has helped a leukemia victim seek a match.

"When I saw the video of Jasmina it broke my heart. It is so unfair that for a black patient it's so much harder to find a bone marrow match," the singer tells PEOPLE exclusively. "Jasmina has acute leukemia and she needs a bone marrow transplant to live."

Last February, Rihanna helped New Yorker Lisa Flynn find a match by putting out a call for donors on PEOPLE.com. "More than 5,000 donors came forward," says Katharina Harf of DKMS, the world's largest nonprofit marrow donor center, which is helping to find a match for Jasmina. "Rihanna has already helped DKMS save many lives," says Harf. "Now we can count on her again."

Rihanna was "very upset" when she learned about Jasmina Amena's struggle with an aggressive and rare form of leukemia, says Harf. "When Rihanna found out about Jasmina, she said, 'I absolutely have to help her.' She wanted to do whatever she could for this little girl. Rihanna loves children and no matter how busy she is, she takes time out of her schedule to help them."

Jasmina’s mother, Thea Amena, who adopted the girl when she was three days old, was "over the moon" when she found out that Rihanna had come forward to help the child find a donor. "My daughter is a huge, huge Rihanna fan," says Amena. "Last year when I was in Best Buy, Jasmina was in the store singing and dancing in front of a huge screen with Rihanna on it. The only way I could pull her away was to buy one of Rihanna's CDs. She's been listening to it ever since."