CALL it a mother's instinct, but after Donna Copson's first baby was born, she knew something was not right. Edward weighed a healthy 9lbs 5ozs at birth, but when Donna took him home, she realised he was having problems with his breathing.

"He used to gag in his sleep. He would be sound asleep next to me in his crib, then I would hear a noise as if he was choking on something," recalled Donna.

She took Edward to the doctor, but nothing was discovered and the mysterious attacks continued.

"I even gave him to my mum for a night because I think the doctors thought it was me being neurotic. Afterwards she said she could never do that again. She came with me to the GP and Edward was first admitted to hospital when he was about four or five weeks old," said Donna.

One suggestion was that Edward had a floppy epiglottis, the bit of cartilage that prevents food from passing into the windpipe when people swallow. After a couple of nights in hospital, he was sent home again, where the choking episodes continued.

"He would snore horrendously. I never needed an intercom," said Donna, of Corfe Mullen.

"He was a very nasal, snuffly baby and when he had a cold, he would go for a couple of nights where it would appear he couldn't breathe properly. You could see his abdomen and chest moving and suddenly, after a couple of minutes, he would gasp.

"Sometimes I would give him eight pillows, sometimes I would give him no pillows. I tried putting him in the recovery position. Sometimes I would shake him."

Edward was referred to a consultant at Poole Hospital. At three, he had his tonsils and adenoids removed and grommets inserted into both ears, but still he did not improve.

A year later, the doctors decided to operate again to check whether they had removed all of the adenoids. During the operation, the anaesthetist had problems keeping Edward oxygenated.

One paediatrician told Donna to cut back on her son's intake of dairy foods. She even paid for her son to be seen privately by an ear, nose and throat specialist, but he could not find out what was wrong.

Eventually, Edward was referred to paediatrician Ann Dewar at Poole Hospital. "He was coming out in septic spots and was always ill because the oxygen was not circulating enough in his system. I took in some photos and a list of all the antibiotics he'd had in the past four years and she said she was going to perform every single test," said Donna.

Edward was finally diagnosed as having obstructive sleep apnoea, in which the airways collapse while the sufferer is asleep. Donna had already come across the condition in her own research.

"I wanted to cry with relief. Suddenly it meant he was going to be treated, that they recognised he had a problem and I was no longer a neurotic mother," she said.

"He'd had five years of acute sleep deprivation because they didn't know what was wrong with him. At nursery his behaviour had suffered. He was constantly tired and angry with the world and he had poor concentration."

At eight, Edward is one of the youngest people known to have obstructive sleep apnoea. It is most common in overweight men who sleep on their backs, but is also thought to be the cause of some cot deaths.

Each time the breathing stops, the sufferer briefly wakes and takes a few deep breaths before falling asleep again. The cycle can continue every minute or so throughout the night.

Edward now sleeps every night wearing a mask attached to a ventilator, which blows down his airway and keeps his breathing clear. He also attends the Sleep Lab at St Michael's Hospital, Bristol, a couple of times a year.

The lab is headed by Professor Peter Fleming, whose ground-breaking research showed that putting babies on their backs to sleep dramatically reduced the numbers dying from cot death.

Recently, Edward's grandmother Jenny Whitney and other fund-raisers donated £600 to the unit, topped up with another £41 from the Casualty make-up team. Donna's brother Marcus is the make-up designer for the programme.

Donna is delighted with the improvement in Edward's health. "He's got a sparkle in his eyes and he's no longer angry with the world. He's got a zest for life he never had before. I'm very lucky to have him," she said.