Charlie was born after 24 weeks and two days inside his mother's womb. That is barely half the normal 40 weeks, and at the outer limit of viability for human life. His lungs were not working, his skin was translucent and his brain was half-formed. He spent the first six months of his life in hospital – four of them on a ventilator – while he suffered repeated crises, contracted meningitis, had a shunt inserted to drain fluid from his brain and struggled to live.
It was a dark time for his parents, Sarah Hyatt-Williams, now 36, a marketing consultant, and her husband, Tristan, 42, a copywriter. "You suddenly find yourself in hospital, surrounded by doctors and nurses telling you your baby is about to be born. They are reeling off statistics about its likely survival and what the risks of disability are if they try to save it. It is not real and you can't take it in," Sarah says.
Each year, thousands of babies are born extremely premature like Charlie, clinging to the edge of life. The numbers are growing – admissions of babies born at 22-25 weeks are up 44 per cent in a decade. In each case, doctors and parents wrestle with an agonising choice: should everything be done to save them, including aggressive intervention, but with a high risk of their suffering long-term disability? Or should they be kept comfortable and cared for and nature be allowed to take its course?
It is a question that has professional ethicists scratching their heads. But Sarah and Tristan, like all parents in their position, did not have time to think. After an uncomfortable night, Sarah had woken with pains in her abdomen. She called Chelsea and Westminster Hospital and was told to come in for a check. She thought she might have a bladder infection and packed her papers for a work meeting, expecting to travel on to her office with a marketing company.
Instead she found herself lying on a bed with the foot end tipped up at 30 degrees in a desperate attempt by doctors to delay the birth. Specialists were summoned, incubators wheeled in (she was expecting twins), monitors hooked up and the full force of modern technological medicine unleashed.
Tristan says: "I remember this neonatal registrar coming in – she was quite abrupt. She says: 'This is a very bad situation. Your baby is going to be born at 24 weeks plus two [days]. Fifty per cent do not survive to leave hospital and among those who do survive only 12 per cent have no disability.' The take-out message was: don't get your hopes up. They may not survive the birth and even if they do, they are highly likely to be disabled."
Sarah says: "I wanted it to be over. It was a bad dream. The likelihood of having a healthy baby seemed so remote I didn't want them to come out alive. That would have taken it out of our hands. It would have been awful but then we could have moved on."
By now, Sarah's contractions were established and there was no turning back. The doctors asked whether they wanted the babies resuscitated should they come out in poor condition. They said no. An hour later, the babies were born – one swiftly following the other.
As they took their first breath, both babies cried. For most parents, that is a moment of joy, signalling the arrival of a new life. But not for Sarah and Tristan.
"It was a nightmare. It meant, 'This is real – it is really happening.' The doctors said, 'You've got a lovely boy.' Then a bit later, 'Now you've got a lovely girl.' It was impossible to take in," Tristan says.
The babies were whisked away to intensive care and they did not see them for 24 hours. Their first visit was not reassuring. In place of the fat, glossy newborns whom parents typically coo over, their babies looked ancient, withered.
"Their skin was translucent, they were hooked up to machines and they were so tiny. You can't imagine it's a real baby. I felt negative. I still wanted it to be over – I didn't want to prolong it," Sarah says.
After nine days, the second twin to be born, Honey, died, succumbing to a virulent gut infection called necrotising enterocolitis (NEC).
Sarah says: "This is what we knew would happen, and it was happening. The 50 per cent who died."
Charlie battled on. But in the ensuing months, he had so many problems including meningitis, hydrocephalus (swelling of the brain) and NEC (like his sister) that his parents wondered more than once whether it was right to continue. Figures show that 70 per cent of extremely premature babies who die in intensive care do so as a result of a decision to withdraw treatment.
Tristan says: "We asked: is it worth going on? Even the nurses were clearly thinking the same – because he was so unwell. But the doctors made it clear that we were not at the stage where there was no hope. "
The rollercoaster continued, from highs to lows and back again. They took Charlie home and brought him back. Only then did the possibility of parenthood begin to dawn. Sarah says: "Once he is off the ventilator and out of hospital and you have brought him home and fed him, then he is your baby. You want to do everything in your power to save him. But until you leave hospital, you don't think you ever will."
At one point, after four months, they were discharged from hospital, only to be chased down the corridor by a nurse as they approached the exit. A brain scan had revealed a new problem. They were transferred to the neurological unit at King's College Hospital, where they remained for another two months.
Sarah says: "I didn't want to take home a child with no prospect of a good-quality life. We had frank conversations with our doctor but he talked us through. And thank goodness he did."
Today, Charlie fizzes with energy, dancing around the kitchen in his parents' west London home, bringing me a collection of soft toys, like any normal four-year-old. He is small for his age, only a couple of inches taller than his two-and-a-half-year-old sister, Rosie, and his development has been delayed. But with help from speech therapists and physiotherapists he is catching up fast.
It could have been so different. On the day I meet him, an interview with Jane Raca, mother of nine-year-old James, also born at 24 weeks, is published. James is severely disabled and his mother has written a book describing her misery, fury, suicidal thoughts and prolonged depression.
Tristan says: "Charlie defied the odds. That is not to say he got away scot-free but it could have been so much worse." Sarah says: "He has got a magnetism people are drawn to. I think it is because he had to fight in hospital. He acts more mature than he looks. He is doing really well."
See charlierocket.co.uk for a blog about Charlie's birth. 'Standing Up for James', by Jane Raca, can be ordered from standingupforjames.co.uk