A woman from Nigeria has successfully donated her stem cells to help save the life of her sister in Weymouth.
Martha Williams, 26, travelled to the UK to donate stem cells to May Brown, 23, after the Home Office reversed a decision not to issue her with a visa.
The decision to allow her to travel came after more than 60,000 people signed an online petition in October.
Mrs Brown said: "I will forever be grateful to the great British public for the support."
The African Caribbean Leukaemia Trust (ACLT) confirmed the transplant took place at King's College Hospital in London.
The operation was postponed from December after Mrs Brown became unwell with a virus and required further chemotherapy, ACLT said.
She said: "I am overwhelmed the transplant has taken place. This opportunity has given me a second chance at life."
Mrs Brown, who lives with her husband Mike and two-year old daughter Selina-May, was diagnosed with leukaemia in July 2015.
She had been told her only chance of survival was an urgent stem-cell transplant. Her sister Martha was a "10 out of 10" tissue match.
The ACLT said Ms Williams was initially refused a UK visa because her teacher's salary of £222 per month was too low.