Stem cell donor raising funds for bone marrow registry with Robben Island swim 5 April 2021 3:37 PM Share This: Christine Roos has been training mainly in a gym pool in Benoni: 'Imagine how many lengths I have to swim before I reach 7.4 km!' A passionate swimmer and philanthropist from Benoni is set to swim from Robben Island to Big Bay to raise R50,000 for the South African Bone Marrow Registry (SABMR). In line with the latest weather forecast, 29-year-old Christine Roos will brave the cold Atlantic on Wednesday 7 April for the 7.4 km swim. A bone marrow transplant can save the life of someone with leukaemia or other blood diseases, and immune disorders.