A four-year-old boy was diagnosed with a rare cancer after chickenpox symptoms failed to clear up.
Calum Rae had chickenpox in January and when symptoms persisted his GP said it was a post-viral infection linked to shingles.
But the symptoms got worse, and the family, from Troon, South Ayrshire, were devastated to be told it was Stage M high-risk Neuroblastoma, an aggressive cancer with a high cancer of recurring.
Calum has had five cycles of chemo since he was diagnosed on March 1 - and in that time has learnt to ride a bike.
His parents, Victoria MacDonald, 33, and Andrew Rae, 35, began fundraising to get him on a vaccine trial at Memorial Sloan Kettering Cancer Centre in New York.
The vaccine hopes to train the immune system to identify and destroy neuroblastoma cells and costs £250,000 as it involves seven trips to New York in a year.
Generous donors raised more than £23,000 in just two days.
Calum will need surgery to remove a tumour in his adrenal gland, close to the spinal cord before he can go to America.
Mum-of-two Victoria said: "It's so sad, it's just a total shock.
"He got unwell at the start of January with chickenpox but it just didn't go away.
"The symptoms were like a condition linked to shingles - he was still lethargic and had leg pain and complained his body was sore, complete loss of appetite, everything fitted in.
"After about a month he had really high temperature fluctuations and night sweats.
"We thought it was post-herpetic neuralgia, a side effect most common with shingles - but when other ones started coming on we thought it was something else.
"The GP sent us to hospital as it wasn't going away and they did an MRI.
"It was horrible, the type of cancer as well is really aggressive and the survival rate in five years is 40 per cent or 50 per cent.
"We are trying to do normal things and to stay positive."
As well as looking after Calum, Victoria and Andy have a five-month-old baby, Emily.
Primary school teacher Victoria said it was a lot of juggling with the new baby when Calum was admitted to Glasgow's Royal Hospital for Children.
Victoria said: "We were really stressed but are kind of functioning better now.
"Our baby was born at the start of November and was two-months old when Calum got chickenpox.
"All the symptoms fitted but it was about a month or so when he got really unwell.
"At one point we thought about taking him to A&E but we took him to the GP and she referred him that day.
"When we were first there he was in so much pain, we had to hold his neck, stomach and back just to comfort him.
"He started chemo and the pain just disappeared. Calum has been lucky as he has been quite well throughout.
"He's on cycle five now, it's every ten days. He needs surgery to remove the tumour which is above the kidney, in the adrenal gland.
"It is leftover cells from when he was in the womb. This cancer is most common in under-fives.
"Because it's so aggressive by the time they show symptoms it has already spread.
"It responds really well to treatment but scientists can't work out why it comes back.
"Only 100 kids a year in the UK get it, I think they don't understand it yet.
"We are almost glad he got chickenpox as it helped to bring it to attention. Calum has been so brave and resilient, that gives us hope and strength.
"He wants to play and he learnt to ride a bike through all this. We have to be strong for him and keep things as normal as possible.
"We have to be happy and to be positive, and hope he will be one of the lucky ones."
The family have not yet applied for the vaccine trial as Calum's NHS treatment needs to finish first.
Victoria said: "We are keen to do anything we can to get the vaccine.
"He has to be disease-free first. It is in trial stages but it is another thing to try and give him the best chance.
"If we didn't try it would just eat us alive. We haven't even contacted them yet but have raised nearly £23,000 in two days.
"It's the power of social media."
The family's JustGiving page can be found here.
