Jessie J shared her grief over Twitter after 7-year-old Daniel Sullivan died of cancer last week.
Daniel had met the singer in July, after a charity arranged for him join Jessie on stage at one of her concerts. The two sang 'LaserLight' together which was a wish come true for Daniel, who was diagnosed with diagnosed with a rare aggressive form of leukaemia.
Sadly, Daniel passed away last week, and Jessie took to Twitter.
She uploaded a photo of the boy, and wrote: "RIP Daniel. I will never forget meeting you and us singing on stage together. Never forget you dude."
Jessie posted the photo of her with Daniel on her Twitter page.
Back in July, Daniel's mother Gillian spoke to the Hartlepool Mail about the experience after organising it with the help of the Believe In Magic charity.
She said, "He loves her, and thought it was great when she allowed him to sit on the stage at her concert in Shrewsbury. I think he was gobsmacked, but he loved every minute of it.
"She asked him to sing alongside her, he thought it was great in front of so many people.
"Jessie J was really down to earth, she spent about half an hour fussing over Dan and she couldn’t have been nicer. We really appreciate all the efforts she and the charity went to."
Watch a video below of the two on stage together:
Photos: the many faces of Jessie J