Like thousands of families across the world, a mother and daughter excitedly wrote their Christmas letter to Santa.

But unlike most, Nicola Thomas-Langlands and her eight-year-old, Megan, are aware they already had the greatest gift of all.

According to doctors neither Nicola nor Megan should be here.

Nicola, 30, was the first heart-and-lung transplant patient to successfully give birth.

She had been born with half a heart and was so ill by the time she was 12 that she was given just three weeks to live. Then a donor was found and Nicola's life was saved.

Nicola, from Eastbourne, said: "Before the transplant I couldn't do anything for myself. I couldn't walk, go upstairs, go to the toilet."

After the transplant her body tried to cope with the new organs and puberty and doctors told her and her parents she probably had another five years to live.

But Nicola felt a sense of duty not to waste the life she had been given. She planned for her future and hoped for a husband but never dreamed of children, thinking it was too much to expect.

Ten years ago she met her husband Neil Thomas, now 28 and working in the IT department at the South East Coast Ambulance Service in Lewes.

After two years they were shocked when doctors told them Nicola was three-and-a-half months pregnant.

Nicola said: "The doctors told me it would put too much strain on my heart and lungs. But I was determined and kept myself active, looking after my new organs as my donor had done.

"Complications meant I had to spend the last four months of the pregnancy at the Conquest Hospital in Hastings with emergency visits to Harefield Hospital in Middlesex.

"I was even told I could have a heart attack during the birth. At low points I wondered what on earth I was doing."

But Nicola was determined and her doctors told her she was going to give birth naturally on her due date.

On July 11 1998 Megan was born. But the birth took its toll on Nicola's health.

"My lungs have been damaged by the pregnancy and I can't do a lot of the things I want to do with Megan. But she understands.

"Since she was three she has become my carer. She strips the beds, loads the dishwasher, does the laundry and the shopping. She gets the bus to school and every day asks me if I will be all right today on my own.

"She says she was sent here to look after me. She is a perfect miracle. In many ways Megan and I should not be here. But thanks to someone else I have gone on to find the most important things in life - a wonderful, loving husband and child. In this I know I have been much luckier than most."

Nicola added: "I met the family who made my life possible and said thank you so many times.

"They took great joy in meeting Megan, knowing she is here thanks to them and their loved one. I want my story to be an inspiration to all those waiting for an organ and to those families who have been asked to donate the organs of a loved one."

More than 8,000 people in the UK are awaiting organ transplants. Due to the chronic shortage 450 will die waiting.

Nicola is backing the Live Life Then Give Life campaign in asking everyone to show the true spirit of Christmas and sign the Organ Donor Register.

To sign up, visit www.uktransplant.org.uk or phone 0845 6060400. Also visit www.livelifethengivelife.co.uk