A little girl with a rare bone disorder brought Simon Cowell to tears with a heart-wrenching solo on The X Factor's Christmas single.

Hallie Robb, an eight-year-old from Herne Bay, is blind as a result of a rare genetic disorder.

Hallie's solo on the X Factor Celebrity final

But the youngster, who is passionate about singing, was given the chance to fulfil a lifelong dream when she was scouted by the notoriously stony X Factor judge at a hospice in Sittingbourne.

Hallie has osteopetrosis - a rare life-limiting condition that affects the bone marrow and can result in bone fractures, restricted height, frequent infections, sight loss and hearing impairment. She is frequently treated at the Kent & Canterbury Hospital.

Her mum Meg Janes, 28, told KentOnline: "We don't know much about Hallie's outcome, her future.

"We know it will affect her brain ultimately, but because it is so rare there is no doctor who can tell us when, how, or what.

"Hallie was born blind. We didn't realise until she was about six months, and she started using her cane when she was about two.

"She had a bone marrow transplant in 2014, and since then she hasn't stopped singing."

Last month, Simon Cowell paid a surprise visit to Demelza Hospice, which Hallie attends.

"They knew she'd want to sing," said Meg, of Neville Road. "She just loves performing. It's always been her dream. She's always said she wants to be a star.

"Simon spent time with all the families individually - he was genuinely so lovely. It came to Hallie, and he said, 'I heard you want to sing for me Hallie'.

"She said, 'well I do, but I'll sing in five minutes'. That's Hallie all over - she kept him waiting."

The X-Factor judge was left stunned by the little girl's rendition of A Million Dreams, from the soundtrack of The Greatest Showman.

"He stood up and said he was blown away," said Meg. "He gave her a pretend golden buzzer. She was over the moon.

"Then he said, 'I want you on one of my shows'."

A week later, Hallie was invited to perform a solo on the X Factor's charity Christmas single - a cover of Snow Patrol's Run. The "ecstatic" little girl was given just three days to practice the lyrics, before heading to a studio in London to record the piece.

A video of the song was broadcast live on ITV's X Factor Celebrity final on Saturday night, with Hallie, her mum Meg, dad Ian, and brother Logan in the crowd.

The tearjerking video, created to raise money for Together For Short Lives and Shooting Star Children's Hospices, features a montage of poorly young children in hospice care, alongside celebrity contestants.

It ends with a solo by Hallie - the only child to perform in the video - using Braille to read the lyrics she beautifully sings.

"It was very overwhelming," said her mum. "We were extremely proud. We've always told her that despite her disabilities she can achieve anything, and I think this proved that to her."

The screening prompted an emotional response from the audience and judges - with Simon Cowell, a patron of Together For Short Lives, breaking down in tears.

Since taking part, Hallie has taken up singing lessons, and hopes to perform on stage in future.

Ryan Campbell, Chief Executive at Demelza Hospice Care for Children, said: "A huge thank you to Simon for not only taking the time out of his busy schedule to spend his afternoon at Demelza, talking to our children, families, siblings and staff but for also giving Hallie the opportunity to fulfil her lifelong ambition and make precious memories for her and her family."

Demelza provides specialist care and emotional support for children with terminal conditions and their loved ones throughout Kent and the south-east.

It is currently aiming to raise £30,000 in this year’s Christmas appeal to support their Care at Home project. To donate, please visit the charity's website (www.demelza.org.uk/Christmas).

Read more: All the latest news from Herne Bay

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