Nicky and Neil Halford, both 36, were left heartbroken when their son Ben, five, lost his three-year battle with cancer. Nicky is a carrier of the rare Li-Fraumeni cancer gene and fought off breast cancer at the age of 21. But the couple, from Coleford, Somerset, didn't know the gene existed until Ben's diagnosis.
Ben asked his parents for a sibling before he died and Nicky and Neil were told by doctors that they could have special IVF treatment, where embryos are screened for the faulty gene before being put back into the womb.
The controversial treatment means that a baby can be born free from cancer that it would otherwise inherit. Only two embryos were suitable for testing - one had the gene, the other didn't. The second embryo was implanted into Nicky and two years after the loss of Ben, Nick gave birth to a boy, Tom.
"We only had one embryo so it really was one chance," explains Nicky.
We tried not to get our hopes up. We'd been through so much that we felt if it's meant to be, it's meant to be. When I found out I was pregnant, we both burst into tears.
Before the couple had Ben, they visited Nicky's consultant to ask if their children might get cancer because she had been so young herself when she had the disease. But they were reassured it was just a 'fluke' although, they were told they would probably struggle to conceive because of the effects of Nicky's cancer treatment.
"We didn't want to pass on anything to our child so that's why we asked the question," says Nicky. "When Ben was born he was healthy for the first 18 months. It was only a month later that things gradually started changing. He became irritable. He was crying for no reason. We were told it was just the terrible twos."
Ben kept losing his balance, so his parents took him to the hospital, and the couple were then given the devastating news that he had a tumour the size of a grapefruit in his brain. Surgeons were able to remove 95 per cent of the tumour and Ben was given chemotherapy to reduce the rest.
After Ben's diagnosis, Nicky insisted doctors ran tests, and it was then it was discovered they both had the faulty gene. The gene is so rare there have only been a handful of cases in the UK. It makes sufferers more susceptible to cancer, especially leukemia, brain and breast cancer.
A scan in September 2007 showed Ben's tumour had gone, but three months later, it had grown back. Doctors operated for a second time and Ben underwent a course of radiotherapy in early 2008. It appeared Ben had beaten the cancer and it was around this time the couple started talking about having another baby.
"I'd asked Ben if he would like another brother or sister and he said yes. He said yes - baby Tom," says Nicky. "We started looking at what we could do. The genetics team at the hospital talked to us about our options. We could take a chance but why should a child go through that?"
Nicky and Neil applied for funding to pay for the selective IVF treatment, which is known as Pre-Implantation Diagnosis (PGD), and a year later they found out they were eligible. But during that time Ben's cancer returned and the couple put their IVF plans on hold.
Surgeons removed the tumour and Ben remained cancer-free for almost a year.
"He had his best year but in January 2010, the tumour came back yet again. This time surgeons couldn't operate because it had spread," explains Neil.
In October 2010, a month after a dream trip to Disneyland, Ben tragically died.
Nicky and Neil decided to wait a year before starting the IVF treatment and, in October last year, they travelled to a clinic in London. The embryo without the defect was then implanted into Nicky's womb and two months later, she fell pregnant.
"I found it very hard because of the memories it brought back," says Nicky.
When we found out we were having a boy, we both broke down. Tom looks like Ben when he was a baby. He's a bundle of joy. Nothing will ever replace Ben though. We'll never forget him. We still think about him every day.
Thanks to the treatment, eight-week-old Tom now faces only a four per cent risk of developing cancer instead of 50 per cent.
"Some people are against it because they say science should not mess with nature," says Neil. "We wanted to give the best possible chance - that's the reason we had to do it. I've heard of people trying to choose the sex but this was life or death. We couldn't watch another child suffer like Ben did."
This week marks the two-year anniversary of Ben's death and the couple have set up a charity in his memory to provide rehabilitation equipment for seriously ill children in hospital. They have raised £35,000 for three different hospitals so far.
For more information, visit Timeisprecious.org.
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