The brave youngster mentioned live on air by X Factor star Rebecca Ferguson has lost his fight for life.
Leonard Scamp, 10, who had been battling a brain tumour for three years, moved the singer to tears when he visited the studio during rehearsals last Thursday with just days to live.
And on Saturday’s ITV1 show she interrupted presenter Dermot O’Leary to say: “Can I just please say hello to Leonard.”
During the visit, fan Leonard met judges Dannii Minogue, 38, Louis Walsh, 58, and a string of X Factor contestants back stage.
Rebecca, 24, told the Mirror: “When I met Leonard he touched my heart. I made a promise to him that I’d say hello.”
“Leonard was such a spirited and affectionate child and loved his dog and cats. Our lives will feel empty without him.”
Leonard was in remission last year thanks to a gruelling course of chemotherapy. But ten months ago, the cancer struck again and his health deteriorated.
An MRI scan at Great Ormond Street hospital, London, a few weeks ago confirmed there was little more doctors could do.
Judge Simon Cowell, 51, was off sick on the day of the visit. he said yesterday: “My thoughts go to Leonard’s family. I’m sorry I wasn’t there to meet him.”
Local residents have also paid tribute.
Theresa Avery said: “He was such a lovely little lad. We thought he had longer but life can be cruel. Our thoughts go out to Melissa and her family.”
Former Head-teacher at Purfleet primary school, Alan Cass said: “Len was such a lovely little lad. My thoughts are with the family.”
A celebration afternoon is still planned for Saturday afternoon at St Stephen’s church in Purfleet.