The Umbrella singer helped find Jasmina Anema - who was diagnosed with NK cell leukaemia, a particularly aggressive and rare form of the cancer, 13 months ago - a compatible donor for her bone marrow transplant last year and is "heartbroken" after she lost her fight for life on Wednesday.

Rihanna said: "I am incredibly heartbroken that Jasmina has passed away. She was such a brave and special child. She showed more strength and spirit than many adults I have met. I feel blessed that I was able to have her in my life, and know that through her example she has saved many lives. She was truly an angel on earth."