It started out as a common cold, but it ended in a double nightmare that has left a mother's world in ruins.

Nurse Amber Selvey was devastated after her "fit and healthy" husband Jason, 47, went to bed with a minorcough and a cold. Just six years later, her son Daniel died in the same tragic way, just days before he turned 25, after suffering sudden heart failure.

Now, the heartbroken nurse is speaking out about the "massive shock" of losing her boys to the same invisible killer. "When my husband passed away, it was a massive shock – really unexpected," Amber said. "When you essentially have somebody who's fit and well and not experiencing any problems, it's not what you expect in life."

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Amber revealed that Jason had gone to bed with what seemed like a minor illness but "wasn't breathing right" when he woke up. Tragically, he "passed away quite quickly after that" in 2017.

Devastated, the mum says she found the strength to carry on through caring for their five children and her job as a children's nurse.

But tragedy struck again as Daniel collapsed at home after suffering heart failure, with Amber managing to resuscitate him. After his cardiac arrest in 2021, Daniel had started to experience chest pains, along with seizures, and this worsened during the pandemic.

And just two years later, he died in his sleep, despite being a very active and fit young man.

Daniel had suffered breathing difficulties as a baby, and doctors diagnosed the tot with the heart condition aortic valve stenosis. After their second child had a different heart condition, Amber pushed for genetic testing

Tests revealed Jason and Daniel had Alagille Syndrome, which often goes unnoticed. Primary symptoms include cardiac issues and narrow bile ducts, which cause liver issues.

Describing the condition, Amber said: "It's a multi-organ condition. It can be quite mild liver involvement, jaundice, to needing a liver transplant. The other main issue is cardiac. There are lots of things that can be put down to other causes, which makes it difficult for people to diagnose it. My husband didn't know he had it until the children were tested."

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According to Amber, Jason, a locksmith, was told the disorder had only affected his liver mildly and not his heart. But his post-mortem showed he had underdeveloped ventricles, and had suffered cardiac failure. Daniel was known to have a heart defect - thought to be a bicuspid valve. But the post-mortem revealed it was in fact unicuspid - meaning he had only one valve rather than three.

Signs of the condition in children can vary, as the disease affects many different areas of the body. It can cause brittle bones, vitamin deficiencies, bone growth problems, and difficulty hearing, among other issues. Youngsters with the disorder often have a wide brow and a narrow, pointy chin

Her children have required operations to widen their arteries and seal the gaps in their hearts, though they're generally thriving and leading ordinary lives.

Nevertheless, the mum continues to live with the persistent dread that her children could face the same destiny as Jason and Daniel, adding: "It was always in the back of my mind that once it had happened once it could happen again, but you still don't expect to lose a child before you. It is not the natural order of the world. Children should outlive their parents."

Amber is now campaigning for greater understanding of the condition to support others, becoming involved with the Alagille society in America. She said: "Like all syndromes it can be quite mild for some people and quite severe for others. It doesn't make it easy to diagnose. You may just have one symptom. I do think awareness is important because there are probably a lot more people out there that do have the syndrome and aren't aware."

Amber has now set up a bereavement support group in Whitstable to help other parents navigate child loss.

Howard Dove, trustee at The Evie Dove Foundation, said: "Amber's compassion and expertise have a profound impact on children and their families. By funding specialist training for talented paediatric healthcare professionals, like Amber, we can spread Evie's sparkle and help keep compassion at the heart of paediatric care."