Christmas will come early for little William Lloyd when he meets Father Christmas at the grand opening of a grotto iat Emery Gate shopping centre in Chippenham on Saturday.

The two-year-old, of Old Town, Swindon, was born with Dandy Walker syndrome, a congenital brain malformation involving the cerebellum and the fluid-filled spaces around it, which causes him physical and mental problems.

He has to go everywhere in a wheelchair because he cannot walk or support his own weight. He cannot swallow so needs to be fed through a tube, he only has 20 per cent hearing in one ear and 20 per cent sight in one eye, and he also has epilepsy and hydrocephalus.

On Saturday, he will have some festive fun at the event at Emery Gate, where he will be Father Christmas’ guest of honour.

This year, the centre has decided that all profits from the grotto will go to the Rainbow Trust, a charity which supports William as it provides practical and emotional support to families when their child has a life-threatening or terminal illness.

William’s mum, Michelle Thomson, said he was invited after she suggested the charity following a Facebook appeal by centre manager, Nicola Milne, for a cause the grotto could support this year.

“I think it’s fantastic,” said the 27-year-old. “His illness means he probably won’t remember much of it himself, to be fair.

“He likes all the lights and things like that so I think it will be great. He will enjoy it on the day – unfortunately he doesn’t know all the excitement building up to it.”

William was born at John Radcliffe Hospital  in Oxford and now receives care at hospitals around the country. He needs constant supervision from Michelle, who is helped out with housework and the cost of travelling to appointments by the Rainbow Trust.

Michelle said: “They have massively helped us. They do all sorts of work. For us in particular they have offered support going to hospital appointments that are further afield than just Swindon.

“We have appointments that take us to Bristol and Oxford and that sort of thing and it’s really expensive to get over there with a disabled child so they help us there.

“And a worker has come to the house and given me support with the housework because I cannot leave William for two to three minutes at a time because part of the Dandy Walker is that he has breath-holding spells.”

William will be a special guest at Emery Gate’s grotto, which this year will see the addition of the Santa’s elves craft workshop set up by business owner Ben Gregory, the director of Digiprint and co-chairman of Cherish Chippenham. The workshop will run from 10am to 4pm throughout December.