She was a healthy, happy and devoted mum, dedicated to her work as a primary school teacher.

But Fiona Tucker went to sleep one night and never woke up.

Her devastated family were later to learn the 29-year-old from Canterbury had an undiagnosed heart condition.

And, alarmingly, she was one of about 12 people to die across the country in the same week from young sudden cardiac death.

It has been hugely distressing for her loving family and, tragically, she leaves her six-year-old son Cassius without a mother.

“It hit us like a bomb exploding and has changed our lives forever,” said her mum, Janice.

“I kept saying to myself, ‘how could it happen’ because she was so active and healthy?”

Tragedy struck while Janice was in Spain last August, with the dreadful news broken to her by Fiona’s older brother, Robbie.

He described how Fiona had gone to bed while her partner Abraham was downstairs watching television. But when he later went upstairs, he found Fiona lifeless. He called paramedics, but they were unable to revive her.

“When I tell people that up to 15 young people a week die like Fiona, they can’t believe it,” said Janice.

“That’s why it is so important to get the message out, to let people know this can happen so suddenly while someone is sleeping when their heart rate and blood pressure drops.

“The charity Cardiac Risk in the Young (CRY), who have been amazing to us, described it to me as like a light switch being turned off.”

Janice and Steve inevitably still struggle with the loss of their daughter, as do the rest of the family.

'It hit us like a bomb exploding and has changed our lives forever' - Janice Tucker

“We pull together to get through it,” said Janice. “It is desperately sad for Cassius but he is a remarkable little boy and has a beautiful dad.

“We take a crumb of comfort in that she did not suffer in any way, but we wouldn’t want anyone else to go through it.

“I still miss her every day and sometimes I have awful dreams that I can’t find her.”

The family are now anxious to raise awareness of the health issue through CRY, which has been supporting them.

CRY conducts research, especially with athletes, and has a screening programme for families affected by young sudden cardiac death.

It says the results show one in every 300 people tested has a potentially life-threatening condition.

It is also calling on the Government to radically rethink its policy of not offering screening, which it says would help reduce deaths of young people from often-preventable conditions.

It is too late for Fiona, but Janice, who volunteers for Health Watch, hopes other families reading their tragic story will take note of this hidden threat to life and the importance of screening.

Janice and Fiona’s father, Steve, a housing association chief executive, live in Barham.

Fiona lived with them until she met Abraham, a landscape gardener, and the couple made a new home in Aylesham.

Fiona had graduated from the University of Kent with a degree in psychology but then turned to teaching for a career and was working at Worth Primary School at the time of her death.

“It was more of a vocation than a job - she just instinctively loved teaching young children and was devoted to Cassius,” said Janice.

“Everything in her life seemed perfect and she and Abraham were a lovely couple and parents.”

At Fiona’s school, where she liked to read stories to the children, a special chair has been made in her memory.

And family and friends last year completed the London Bridges Walk, raising £1,200 for CRY.

To find out more information about the charity and its screening campaign, go to www.c-r-y.org.uk.

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