My brave son has a unique heart - he's been battling since the day he was born

After eight hours of open-heart surgery, little Chester Osment's heart had to be stopped twice after it raced to a dangerously high 280 beats per minute.

Chester's shocked surgeon told his parents their son's heart was unique and that he had never seen one quite like it before.

Chester was born with the congenital heart condition complete Atrioventricular Septal Defect (AVSD).

Around 13 children are born with heart conditions in the UK each day, according to the British Heart Foundation, but Chester's mum, Kristy Evans, admits she used to assume that only older people could be affected.

Chester has overcome a lot in his first 15 months, including sepsis, Covid and endocarditis, while his mum has also needed to perform life-saving CPR on him.

During his first eight months, the longest Chester spent at home was four days as he underwent surgery, had spells in intensive care and was rushed into hospital battling for his life on a number of occasions.

He is now at home in Blaenavon, Torfaen, growing stronger as he awaits more major surgery - with mum Kristy reflecting on everything he has overcome in his short but eventful life.

"He's defeated the odds in so many ways, he's incredible, so brave," she said.

Kristy said she was initially not overly worried when, in November 2024, a nurse at The Grange Hospital in Cwmbran thought she heard a murmur on Chester's heart, who at the time was just three days old.

Kristy stayed in her hospital bed as partner Ben, 25, went with Chester for scans.

"Ben came back and I knew it was bad - I could see he had been crying and he went straight to the window," said Kristy, 33.

"I remember bursting out crying - I was told he needs surgery but he needs to be stronger.

"I asked the doctor 'is my baby going to die?' and he said 'I can't answer that'."

Chester needed life-saving corrective surgery but needed to be 11lb (5kg) or six months old, to be strong enough to survive it.

But he was just 5lb 7oz (2.59kg) when he was born and had dropped down to 4lb 11oz (2.12kg) in the days that followed.

Complete AVSD is a serious congenital heart defect characterised by a large hole in the centre of the heart.

This allows blood to mix between all four chambers.

Through an abnormal valve, excessive blood also flows to the lungs, which can cause heart failure.

It requires open-heart surgery, usually in early infancy, to repair the defect, fix the valve, and prevent permanent damage to the lungs.

After 10 days in intensive care, doctors allowed Chester to go home so he could put on weight and gain strength ahead of open-heart surgery.

But he was never home for very long.

"In January last year, I was using a feeding tube, but there was a lot of mucus, and he just went blue and floppy," said his mum.

"I called an ambulance. They had taught us CPR [in hospital], and I had to perform it until the ambulance arrived.

"He has been through so much, and when I think of what he's overcome, I think 'oh my goodness'."

Chester was in hospital with Covid in February 2025 and at various other times with viruses, as he was so small and struggling with his weight.

By May, Chester could not keep any food or medication down, was pale, struggling to breathe, and suffering heart failure.

At this stage, he was 4.7kg (10.3lb), and doctors said he could not wait any longer for surgery, so on 2 June, he was taken to hospital in Bristol where he spent eight hours in theatre.

"Seeing Chester put to sleep was so hard, we didn't know if we'd see him alive again," said Kristy.

"But he did amazingly. His cardiac surgeon said Chester's heart was unique and he'd never seen anything like it before."

But a few days after surgery, Chester's heart raced to 280-beats-per-minute twice within the space of a few minutes.

This is called Supraventricular Tachycardia and doctors explained this could happen after open-heart surgery.

It was reset with medication injected through his veins.

Chester would not return home until 8 July, as he spent the next two weeks battling sepsis and the rare, life-threatening infection of the heart's inner lining endocarditis.

The surgeons had been able to patch up the holes in his heart and created valves, but they are leaking badly, with his condition managed by medication.

"He's stable now but it's daunting how rapidly it can go into heart failure - it could be weeks, or years," his mother said.

Chester, who is now 8kg (17.6lb), needs to be 10kg (22lb) to undergo surgery to have mechanised valves fitted to his heart - and he will then need them adapted through his life as he grows.

Kristy, who has two other children, aged 12 and eight, said: "He's behind on his development, and can't crawl, only lies down.

"But he's such a strong little boy, so happy and smiling. He loves Shrek, and we've got horses, he loves the Spirit horse films.

"After Chester, it makes you realise heart disease isn't just for later in life, babies like Chester are born fighting from day one."

During February, Kristy and Doberman Raven are attempting to walk 100 miles to raise money for life-saving research, accompanied by Chester in his pram.

June Davison, Senior Cardiac Nurse at the British Heart Foundation (BHF), said: "When BHF was founded in 1961, the majority of babies diagnosed with a severe heart defect in the UK did not survive to their first birthday.

"Today, thanks to research, more than eight out of ten survive to adulthood."

Davison said many children would need repeat operations as they got older and some would have limitations in their everyday life.

"[But] many people with congenital heart disease can live a full and active life," she added.