A brave band of brothers from Norfolk have just completed the run of their lives to help save the life of a baby girl who weighed just 470 grams when she was born four months prematurely.

Isla Briggs is now six months old but has only just broken through the 5lb barrier and continues to fight, as she has done every day since April, to fend off infection and stay alive.

In celebration of the tiny tot's gigantic heart and courage her father Nick, 33, and uncles Jonathan, 38, Tim, 37, and James, 35, took part in the Royal Parks Foundation Half Marathon in London to raise money for the First-Touch charity and help provide neonatal equipment which helped Isla when she was in a critical condition and will help countless others like her.

The brothers, who completed the run in London last weekend all wearing oversized nappies, helped raise almost �15,000 which will go towards purchasing a specialist incubator which is used to transport critically ill premature babies to specialist hospitals.

Nick, who used to live in Taverham and attended Notre Dame High School in Norwich before going to Gresham's School near Holt, said: 'We're going through this with Isla and one of the brothers said we should really just try and give something back to the hospitals that looked after her.

'Isla was in a critical condition and only through the support and skill of the staff is she here today. You don't really have any idea of the cost of all the equipment that's around you. The incubator costs �36,000 and it was something tangible which we thought we could help with.'

The run proved to be a major test for all four brothers not just of their physical endurance but of their mental and emotional strength too.

Nick, a marketing manager for a telecom company in London, said: 'I can't believe all four of us ran – it's the first time we have all competed in the same event before. Out of the four brothers I think I was the slowest, but we all ran over the line together.

'It was an amazingly emotional day. It was the first time all the family had got together and talked about it. To be able to say to First-Touch we have been able to raise nearly half the money they need, just from one event, is unbelievable.

'I actually saw one of these transport incubator machines moving a new recruit into the unit and my heart starting beating pretty fast as this reminded me of five months ago when our own dear little Isla was moved from the hospital in Chertsey to St George's.

'I just want to really thank everyone who had supported us during this difficult time. Isla is a fighter and is an inspiration to us all.'

The past six months has all been a bit of a blur for Nick and his wife Phi, 31, who married in May 2009, and who have spent almost every day travelling from their home in Surrey to be by their brave daughter's side.

Nick, whose parents Peter and Kathy live at Little Melton, said his wife had enjoyed a normal pregnancy for the first five months and the couple had no inkling about the drama that was about to follow.

He said: 'All was going well, my wife had four months to go and we had just moved from London to Surrey. My parents were coming from Norwich for the first time to see our house, I was out buying wine and my wife phoned me complaining of backache. 'She called back 10 minutes later and told me to call an ambulance.'

Nick said by the time they got to the Royal Surrey County Hospital in Guilford his wife was taken immediately to the maternity ward and by 6.20pm on April 24 Isla was born.

He said: 'She wasn't breathing much and there was a lot of shaking of heads as if to say she wasn't going to survive, then after about 15minutes Isla decided to have a go herself.

'They needed to move her to a specialist hospital so we had to go to St Peter's Hospital in Chertsey which had a higher level of premature baby care.'

Isla spent the next three weeks battling for her tiny life at the hospital in Chertsey before being moved again to St George's Hospital in Tooting, London, where she remains today.

In the early weeks and months of her life she had to three times fight off the life-threatening Necrotizing enterocolitis which is a gastrointestinal disease that mostly affects premature babies.

NEC involves infection and inflammation that causes destruction of the bowel or part of the bowel. Although it affects only one in 2,000 to 4,000 births, or between 1pc and 5pc neonatal intensive care unit (NICU) admissions, NEC is the most common and serious gastrointestinal disorder among preterm infants.

Nick said: 'Isla had a life threatening battle with it one night and turned very pale and we were told they did not think she would survive the night.

'They gave her antibiotics then it's really up to the baby to fight it off which she has done three times now. It's absolutely heart wrenching when it happens. She's had a couple of operations to cut out the bad bits of gut and reattach the good bits.

'She's fought it three times but there's always the chance she won't win the battle. It's still a bit of a waiting game but she broke through the 5 lb barrier last weekend just before we did the run which for us was a real turning point.

'She's come a long way. When you get to see her you just think something as small as her has fought all this. There's nothing we can really do apart from support her.'

Nick said his daughter has showed extraordinary determination to survive which has inspired not only him but everyone who has met her or knows her.

'All the family and friends say what an amazing little fighter she is and that really does sum her up. She's just a complete miracle really. 'We're extremely lucky to be where we are today, but we're not out of the woods yet.'

Isla who spent much of her first six months in a critical condition is still in a cot in hospital, although with some of her wires removed her proud parents have been able to enjoy the odd precious cuddle.

It will however be some time yet before Isla can be discharged from hospital where she is receiving round the clock care from expert staff.

It is that level of care which inspired Nick and his brothers to take part in their half marathon challenge last week and will keep them looking to find other ways of raising money in the future.

Next month Nick's brother Jonathan and his wife Carey, who live at Weston Longville, near Lenwade, will be taking part in the Norwich Half Marathon from the Norfolk Showground to raise even more money for the First-Touch charity.

Anyone who wants to find out more about the charity or how to help should log onto www.first-touch.org.uk

The fundraising website is still open for donations and can be found at www.justgiving.comsupportingbabies-at-stgeorges

Are you raising money in recognition of the help or care a loved one has received? Call reporter Peter Walsh on 01603 772436 or email peter.walsh@archant.co.uk