Toby Nye, of Osmondthorpe, was diagnosed with stage 4 neuroblastoma on his fourth birthday in January.
He underwent a ten-hour operation to remove a tumour from his kidney earlier this month and is currently in Leeds General Infirmary following 12 sessions of high dose chemotherapy.
His family is staging Toby’s Christmas Charity Ball and Auction on Saturday November 25 at the Queens Hotel as they continue trying to raise £200,000 to pay for antibody therapy not currently widely available on the NHS.
A series of fundraising events have already raised almost £40,000 for the well-supported appeal..
Toby’s father Simon Nye, 30 and mother Stacey Worsley, said Toby is “cheeky, chatty and always smiling.”
Miss Worsley, 30, who works as an elderly care nurse at St James’s Hospital, said: “We just take it day by day. It is very upsetting and we have our times when we break down and get it out of our system but then we pull ourselves together and carry on.
She added: “There are people we don’t even know who are fundraising for Toby. It’s really overwhelming.”
Toby’s uncle Chris Cash, 50, of Crossgates, is organising the charity ball, which is set to be attended by two Coronation Street stars and Leeds boxer Josh Warrington, who has visited Toby in hospital.
Adele tribute act Joanne Copeman and comedian Jed Stone will be appearing at the event.
Among auction items will be a four-night stay at a five-star hotel in New York plus flights; boxing gloves signed by Floyd Mayweather and Josh Warrington and a football boot signed by England World Cup hero Geoff Hurst.
Mr Cash, who is appealing to local businesses to donate more auction items, said: “It is heartbreaking to see what Toby is going through.”
Tickets, priced at £50, are available by calling Chris Cash on 07831 351693. To donate to the appeal, go to www.justgiving.com/crowdfunding/sheriden-worsley