It was just after Christmas 2003 when six-year-old Kailee Wells looked up at her mother Linda and said: 'Mommy, I am going to miss you when I die.' They were words that no mother ever wants to hear; words that were like a knife stabbing into Linda's heart. She felt like crying. Instead she gulped, held back her tears and told her daughter: 'Sweetheart, mummies usually die before their little girls and I will miss you terribly.' Inside, Linda knew there was a very strong possibility Kailee was right. The child had been diagnosed with life-threatening severe aplastic anaemia when she was five. On many occasions, doctors had taken Linda and her husband, Owen, aside and told them their daughter had only days or weeks to live. But Linda and Owen never gave up hope of seeing their daughter healthy and living a normal life. 'We always believed we were going to keep our girl and we had to keep fighting for her,' Mr Wells told the Sunday Morning Post last week. 'If she was going to make it through, then, by God, we were going to save her.' It was this fighting spirit which took the Wellses on a journey away from their home in Albuquerque, New Mexico, across the world to mainland China, where Kailee's plight touched the hearts of thousands of people - including the one man who was eventually to save her life. In 2002, Kailee was diagnosed with the rare and potentially fatal blood condition similar to leukaemia, in which her bone marrow could not produce enough blood cells. A bone marrow transplant was her only chance of survival. A biological sibling would have had a one in four chance of being a match for the transplant. But Kailee's case was complicated by the fact that her biological family was unknown. She was born in Hunan province in 1997 and, at 10 days old, abandoned on the steps of a teacher training college. The Wellses fell in love with her and adopted her, taking her back to the United States a year later. Without a biological family match, the Wellses had to rely on the existing bone marrow donor registers. Again, this was complicated by the fact that few ethnic Chinese donors were recorded on the registers in the US, drastically reducing their chances of finding the right match. 'We were told the odds of finding a donor were 10 million to one,' Mr Wells says. 'The Chinese Marrow Donor Programme had barely started and only had something like 20,000 names on their register.' By 2003, when the register still failed to turn up a donor, Mrs Wells took a brave step and set out on a mission to mainland China to track down a biological sibling of Kailee. Her mission was unsuccessful, but it attracted the attention of the local media and Kailee became the focus of a campaign by the Red Cross Society of China to encourage more people to come forward and sign up as donors. The number of names in the Chinese Marrow Donor Programme grew. In 2005, a match was found. But it was not perfect and, although doctors went ahead with the transplant, it was rejected by Kailee's body. In September 2005, the Wellses prepared to go to the mainland again on another recruitment campaign. They were ready to leave with their bags packed when the news came through that a perfect genetic match had been found. Wang Lin, a 28-year-old doctor from the eastern city of Hangzhou , had walked into a blood donor clinic and offered to become a donor. He was that one-in-10-million person who could save Kailee's life. 'It was literally the day before we were due to leave when we learned we had the perfect match in Dr Wang Lin,' Mr Wells says. 'It was amazing. We were in a state of disbelief for days.' Kailee underwent a successful transplant in November 2005 with the bone marrow donated by Dr Wang. She had a second transplant from him earlier this year to solve a few problems. Today, Kailee, who now lives with her family in Milwaukee, Wisconsin, is well and happy and looking forward to Christmas like any normal 10-year-old. 'She is doing well,' Mr Wells says. 'She is now a fifth-grader at school and is on the honour roll, which is amazing when you consider all the school she has missed - half a year every year for six years.' She is also well enough to travel and last week made her first return trip to the land of her birth for an emotional meeting with the man who saved her life. At the event, organised by the Red Cross Society of China, Kailee presented a tearful Dr Wang with a picture frame inscribed with the words: 'You are my hero. I will love you forever.' In response, the doctor swept Kailee up in a big hug. 'To see her standing before me, I feel so moved, so happy,' he said. 'The fact that we could be matched among this sea of people is a matter of fate.' For the Wellses, the experience of meeting the man they had spent almost four years searching for was overwhelming. 'It was a honour to meet him,' Mr Wells says. 'He is a very compassionate and gentle person. We called him 'our special daddy'. We really hope we can keep in touch with him and share our lives with him as Kailee gets older.' This Christmas will be an extra-special one for Kailee. As well as getting to know her birth country by spending the holiday with her family there, she will also be taking time to recruit more marrow donors. It is her family's way of thanking the Chinese Marrow Donor Programme, which now has 700,000 donors on its register. 'Kailee is such a wonderful child,' Mr Wells says. 'She has given us so much happiness and now she is having the chance to be normal again. 'She is enjoying the experience very much of being in China. It's a place we have a special bond with. China has given Kailee life twice and we feel very blessed.'