Pop sensations One Direction may sing Best Song Ever but they made certain Gravesend youngster Stacey Mowle had the best day ever when she met them during a private studio rehearsal.

Stacey was thrilled to chat and have photographs taken with her idol Harry Styles and his fellow band members Liam Payne, Louis Tomlinson, Zayn Malik and Niall Horan.

And if that was not thrilling enough for the youngster, Harry put the icing on the cake when, just days later, he sent her a special video message for her 8th birthday.

The youngster’s surprise ‘date’ with the band was organised by X Factor finalist Tamera Foster, also from Gravesend, and her mum Rachael.

Tamera, 16, has formed a special friendship with Stacey, who is fighting a type of cancer for which neither treatment nor NHS funding is available in the UK.

Her family have launched an appeal to raise £500,000 for treatment in the US.

Harry was the first to greet Stacey at The Fountain Studios in Wembley - home to the X Factor live shows.

And the youngster, who suffers from relapsed neuroblastoma, took great delight in telling the 19-year-old they were wearing matching stripey tops.

Stacey’s dad, Warren, said: “Harry came straight over in his long black coat for a quick photo.

“He said: ‘Hello Stacey it’s nice to meet you.’ Stacey was over the moon, and in shock, I think.”

Stacey and her dad were accompanied to the studios by mum Samantha, 32, and 10-year-old brother Jake.

In an exclusive interview, Warren said: “We had a chat and some amazing photos were taken including Harry and Stacey pulling faces at each other.

“One Direction then rehearsed a few times, which was amazing. It felt like a very private show.

“After they finished they said goodbye to Stacey and Harry told her they were now tied to the hip.

“She found it very hard to sleep that night and when I asked her the next day whether she had had a good day, she said: ‘Thank you Daddy. It was the best day of my life.”

But Warren said it was North West Kent College student Tamera who had to be thanked for all the efforts she went to to help organise Stacey’s special day.

“Tamera made my princess’s dreams really come true,” he said.

“We could never thank her enough and I know that our families will stay friends forever, whatever happens.”

Stacey, of Trafalgar Road, has been receiving high dose chemotherapy at The Royal Marsden Hospital in Surrey, but was given special permission to leave for her day out on Sunday.

Tamera introduced the family to fellow X Factor contestants Rough Copy, Luke Friend, Nicholas McDonald and Sam Callahan, presenter Dermot O’Leary and Xtra Factor presenter Caroline Flack.

“Tamera made my princess’s dreams really come true” - Warren Mowle

The Mowle family also got the chance to sit in the judges’ chairs and watch head judge Gary Barlow rehearsing for his own performance on the live show that evening.

But the fun's fading now, as Tamera practises ahead of X Factor's 10th birthday this weekend.

The final six contestants will be singing some of the biggest hits from the show - including Hallelujah and The Climb.

Tamera will be singing Impossible, which was released by last year's winner James Arthur.