The picture was taken at Jumeirah beach, Dubai, in 2005. It is of a little lad, just two years old, playing in the sand while his doting parents Kevin and Karen Capel look on. Earlier they’d enjoyed breakfast by the Sheraton hotel pool. Later, they spent a couple of hours on the slides and swings in the playground.

It is a snap of a typical family holiday and yet Kevin and Karen cannot look at it, or think about this break without feeling sadness.

It was one of the last times they were truly happy. It was one of the last times their little boy Christopher – who was always smiling and laughing – was fit and well. Just 18 months later he was diagnosed with a brain tumour, sparking a painful, protracted and ultimately failed fight for life.

For another 18 months after that, he would undergo some of the harshest treatments known to medicine in a bid to battle his illness. He’d suffer the heart-rending side effects – baldness, loss of speech, destroyed stomach lining, infection after infection, and hearing damage –that would make any parent shudder.

Ultimately, he would die on June 5, 2008, nine days short of his sixth birthday. Yet, as his parents look at the photos from that family break 
in the sunshine, they are reminded of the pledge they made that his young life would not be in vain.

Christopher inspired them to found a charity, Christopher’s Smile, which has the aim of trying to ensure youngsters do not have to undergo the horrific fight endured by their boy. And, six years after setting it up, they have raised nearly Dh5 million.

“Nothing can bring Christopher back,” says Karen. “But we hope this can make a difference to children like him in the future.”

Kevin, 56, and Karen, 53, still remember with absolute clarity the day they were told four-year-old Christopher had a brain tumour.

He had been sick – and growing gradually worse – for weeks. Vomiting in the morning had turned into intense headaches throughout the day, fatigue and occasional diarrhoea. He had only just started school but had not yet managed to attend for a full week. Tests couldn’t find anything wrong. So, in desperation, on October 23, 2006, specialists at Frimley Park Hospital near the family home in Surrey, in the UK, carried out a brain scan.

It revealed that Christopher had cancer of the brain.

“We were in the corridor when they told us,” says Karen, a language training consultant. “How did it feel? Numbing. You go into shock. Life changes in that single moment. Everything you thought was a priority recedes and all that matters is trying to get your little boy well.”

She pauses. “The daft thing is we knew so little about what a brain tumour meant at that point, I remember my first question was ‘Well, will he be all right?’”

He wasn’t.

Doctors immediately blue-lighted him to St George’s Hospital in south London for an emergency operation. Surgeons were to remove the large growth. But, before they did, they warned of two things.

First, there was no guarantee Christopher would survive the operation. Second, a further scan had shown the cancer had spread to his spine. Even if he survived, he would need to undergo six months of intense chemotherapy.

“It felt like we were receiving one blow after another,” says software engineer Kevin. “We couldn’t think about the chemotherapy at that point because we just had to get through the surgery that day.

“We spent six hours pacing the streets on a wet, miserable day until we received a call saying he had come through and we could go to see him in intensive care. The only words Christopher spoke were, ‘I want to go home’, which of course broke our hearts as it was beyond our control.”

Worse still, these were the last words he was able to speak for weeks. Young children who have brain operations often suffer something called posterior-fossa syndrome where they lose some of their most basic faculties. They’re unable to walk, talk or even retain food. For some time Christopher had to be fed intravenously. At times, he was so weak he couldn’t sit up without rolling over.

“He was essentially thrown back to the day he was born,” says Karen. “It’s devastating. And there’s no guarantee they’ll ever regain those skills, if they’ll ever be able to say your name again. Some children don’t recover from it.”

Christopher remained largely mute until late January. That was long after his chemotherapy started in December.

Chemotherapy can kill the cancer but the side-effects – hair loss, intense nausea, severe abdominal cramps, extreme fatigue, possible infertility, shingles, increased risk of fatal infection, permanent organ damage – are many and painful.

In children, it is, if anything, even more violent. The dose given to youngsters in relation to their body weight is so high that the equivalent in an adult would most likely kill them.

And so Christopher suffered. His hair fell out. His hearing was permanently damaged. He needed feeding via a drip because his stomach lining was completely destroyed.

“There were days and nights where we lost count of the number of times he was sick,” says Karen. “One of the drugs caused a hearing deficit. He suffered unimaginably every day.

“We sat looking at him, wishing for all the world we could take the pain away, that we could suffer so he didn’t have to. And yet he never once complained. The opposite. He didn’t smile much but when he did, it would light up the room. He was a fighter.”

In July, after six months of treatment, there was good news. The therapy had worked, A spinal tap showed he appeared to be clear of cancer. “We were euphoric,” says Karen. “You know nothing is certain. You know there’s still more than a possibility the cancer will come back. But there was some light there.

“During that summer, Christopher learned to eat again and built up strength. He was now talking. More than anything he wanted to play with all his friends again. His hair started to grow back and he started to become stronger and returned to school in September.”

It was, however, not to last. By October, he was falling sick again. 
A routine scan in November revealed the news the family dreaded. The cancer had returned, and spread.

This time, it was advised that chemotherapy alone would not work. It would only cause pain. Kevin and Karen agreed for Christopher to trial a series of new drugs, and while they showed some effect on the speed the cancer was growing, it was, ultimately, still spreading.

And so, in April 2008, the couple found themselves taking the heart-rending decision that, from now on, they would not seek a cure. They would make Christopher’s last days as comfortable as possible.

“You can’t describe how that feels,” says Kevin. “It’s unbearable.”

The idea for Christopher’s Smile came about within weeks of his death. “This wasn’t a way of getting over the pain,” says Kevin. “We will always harbour it because you can’t get over losing your only child. But it does allow us to do something to try to make it so other families don’t have to go through what we did.” While they realised that there is no shortage of people raising funds for cancer charities, they also came to understand that only a tiny proportion of that funding went into children-specific research.

So they decided that Christopher’s Smile would focus on raising money to fund research into drugs that target childhood cancer. And over the past six years it’s done just that – to an even greater extent than either Kevin or Karen could have hoped for.

Through bake sales, sponsored walks and informative talks, they have raised almost Dh5 million.

All that money has gone direct to the cause. Because they run Christopher’s Smile in their spare time, there are no external costs like wages or office rents. Everything they’ve made has been used to fund four full-time research posts at the Institute of Cancer Research (ICR) based in London.

As a direct result of the cash, the ICR was able to increase the number of clinical trials of targeted agents from five in 2010 to more than 20 in 2013. While it would be inaccurate to say these tests have directly led to any one child being saved, they are helping to build medical knowledge that, it is hoped, will one day help to save millions of lives.

“We really value our relationship with Christopher’s Smile – and admire the dedication of Kevin and Karen to help children with cancer,” says Thomas Bland, director of development with the organisation.

And while nothing can bring back that little boy playing on the beach in Jumeirah, the knowledge that they may stop other families suffering keeps driving Kevin and Karen on.

Christopher, they say, was known for his smile. Now, they hope their fundraising will bring a smile to other families.

To find out more log on to: christopherssmile.org.uk