Maia, 13-months old, will donate part of her bone marrow to her two-year-old sister Rhianna.

Rhianna was diagnosed with a blood disorder in February, and her parents Lynne and Dave were told she had less than a year to live unless a match could be found.

Lynne, 33, of Valley Drive, Woodingdean, Brighton, said: "When Rhianna was born she had lots of spots on her chest.

"Although doctors knew something was wrong, they weren't sure what it was.

"In February they found out it was a myelodysplastic disorder, which is very rare and only affects six children a year.

"They said Maia might be able to donate some bone marrow but the chances of it matching were slim."

But last week the couple were told by doctors at Great Ormond Street Hospital, London, that the children's bone marrow matched exactly.

Doctors will transfer a small quantity of blood, containing tiny parts of marrow, from Maia to her sister later this year and believe there is a 70 per cent chance of success.

Lynne, a housewife, said: "It's really hard when you see Rhianna to believe there is anything wrong with her, but her condition means she bruises very easily and her blood can't clot.

"But thanks to Maia and the doctors, she should be able to grow up like any other child."

While waiting to hear the good news, the couple had arranged a session where possible donors could arrange formmarrow samples to be taken and their details passed on to The Anthony Nolan Bone Marrow Trust, based in London.

The event is still going ahead on April 11 between midday and 4pm at Havelock Books and Music, Havelock Road, Brighton.

For further details contact Jackie Chase on 01273 703625.

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