Sir Elton John is backing a campaign to make a charity version of his song Tiny Dancer the Christmas number one in Ireland to raise funds for a little girl with cancer.
The single is performed by some of Ireland's top recording artists, including Paddy Casey, Declan O'Rourke and Camille O'Sullivan, who are among more than 300 musicians to contribute to the track.
It was recorded in aid of four-year-old Lily-Mae Morrison from County Galway, who suffers from neuroblastoma, a rare and high risk form of childhood cancer.
The single - Tiny Dancer by A Song For Lily-Mae - has already spent two weeks at the top of the Irish singles charts, outselling entries from Labrinth, Emeli Sande, Rihanna, Olly Murs and One Direction.
It has become the fastest-selling single in the Irish Republic this year and the fastest-selling non-X Factor single of the last six years.
Sir Elton recorded a special message of support for Lily-Mae and is urging his fans to buy the song.
Money raised will go to the Sunni Mae Trust - to help Lily-Mae and research into neuroblastoma - and the Neuroblastoma Society .
A blog on the Sunni Mae Trust website, giving updates on Lily-Mae's progress, urges people to buy Tiny Dancer and fend off the challenge of the single from X Factor winner James Arthur.
It says: "The X Factor does not need another Christmas number one, neuroblastoma does.
"It needs that number one spot so that it is no longer a disease that no one has ever heard of. So that it gets more research and funding so that hopefully other families don't have to go through what Lily-Mae and her family are going through."
And a Facebook campaign explains: "James Arthur will have an incredible future in the music industry, he already has had the best start of any X Factor winner; Lily-Mae, on the other hand, has an uncertain future, she gets one shot at this, he will have many.
"Please, give Lily-Mae the best possible Christmas present, short of curing her cancer, give her the Christmas No.1!"
Lily-Mae and her parents Judith and Leighton Morrison - both professional ballet dancers - attended the recording of the single, and were delighted at the choice of song.
"Tiny Dancer is one of my partner Judy's favourite songs so we were thrilled to hear that it was going to be released for us," said Mr Morrison.
"We are both ballet dancers and Lily-Mae loves dancing, when she grows up she wants to be a ballet dancer as well. She is our tiny dancer."
Lily-Mae has already undergone surgery to remove seven tumours, but still faces a long haul of stem cell treatment, radiotherapy and immunotherapy.