It is impossible to imagine the agony of walking into the bedroom of your 14-year-old son to try to wake him up only to discover he has died.

Tom Clabburn, a 'live wire' bursting with energy, who played for Hanwell United, went to bed the previous evening 'slightly off colour' and was found by his father Paul the next morning. 

It was the beginning of the horror that shook the family to its core and although it ahs been two years ago since Tom died of an undiagnosed heart condition, the death is something mum Claire Prosser will never get over. 

She said: "When your child dies of leukaemia or cancer you have heard of those things. 

"This was such a shock.  Tom was active, full of beans, very lively and always on the go.  He had never shown any signs of illness. 

"Paul went into his room because he hadn't got up and he was dead.  It was shocking.  I takes you at least two weeks to believe this has really happened. 

"I was in shock for two months - zombied.  The ambulance woman wouldn't look at me.  She just said "I don't normally deal with dead children." 

"Some people say the right thing.  Some don't.  There's no script.  I would rather someone just touched my arm or gave me a hug. 

"At the beginning I thought there will be a solution in books or counselling but you don't get over it.  You just get more used to it." 

Friends and family rallied round, leaving food on the doorstep, and somehow Paul and Claire managed to support each other. 

Claire, of Elers Road, West Ealing, said: "I've heard that around 75 per cent of marriages fail when a child dies. 

"I thought 'That must never happen to us.'  We have a strong relationship and did a lot of walking.  Ellen, our daughter, talks to friends.  There were only 18 months between them and they were close and used to hang out together.  She seems OK.  It might come out when she's older." 

The dynamics have changed irreversibly, making anniversaries and holidays especially hard. 

Claire said: "We went to the seaside and there was no Tom dashing around.  In restaurants there are lots of tables for four. 

"I can't buy boys' clothes any more.  We have gone from a family of four to a lopsided family of three.  this is the new normal." 

Eventually, Claire went back to work as a journalism trainer for the BBC partly to take her mind off things and also in memory of a son who wanted to be a sports journalist. 

There are positives to come out of Tom's death, not least the family's involvement with the charity Cardiac Risk in the Young (CRY), which promotes awareness of sudden death syndrome and sudden cardiac arrest in the young. 

Claire and Paul were desperate to stop this tragedy happening to another family and have raised £20,000 from friends and family. 

They took part in the national Eight Bridges Walk as Team Tom and held a cake and book sale at their home. 

Claire said: "There was no support when Tom died and then a friend mentioned CRY.  The great thing about CRY is that it raises awareness of heart problems and screening but also deals with bereaved families.  We both had phone counselling and Paul wanted to get help with fundraising." 

The couple have sponsored the latest screenings at Brentford FC this weekend (June 26-29) as part of CRY's Test My Heart Tour 09. 

The tour aims to provide the screenings for around 3,000 14 to 35-year-olds all over England. 

Last year Claire made a programme for Radio 4, Life After Tom, which gave her a new focus. 

She said: "As a journalist I wanted to make it interesting but as a mother it was very said and emotional.  One of the most moving moments was when a poem by Tom's friend Joseph was read out.  The response was quite overwhelming. 

"It brought Tom to life, his sense of fun.  I will always be able to look back on his first anniversary with pride, that I made a programme about my son.  He would have been amazed to find himself on Radio 4." 

Her other idea for keeping Tom's name "out there" is rather more extreme: to buy a wood where people can go and watch the seasons change and think about an amazing young man. 

For Claire, Tom is never far away even if he is giving her a gentle reprimand.  Claire said: "Sometimes I hear him in my head saying: "I am bored with the crying.  You are flailing around." 

Counselling help from CRY charity

Cardiac Risk in the Young (CRY) is a charity which offers help and counselling when a young person dies of a sudden undiagnosed heart condition. 

Support includes bereavement counselling, a fast-track service run by consultant cardiologist Dr Sanjay Sharma and the CRY surgery supporters' club. 

The charity also pays for research into the condition. 

There is a database of expert information plus bereavement days and a family conference day where grieving families can learn about the condition and ask questions to the experts. 

Lasts October Claire and Paul joined MPs to launch a national awareness campaign to highlight the shocking figures that there are 12 deaths every week. 

CRY unveiled a poster-sized version of a postcard at a ceremony outside the House of Commons featuring 12 young people from London and the South-east who had lost their lives. 

CRY is rapidly gaining MPs' support with an All Party Group for Cardiac Risk in the Young, a proposed private member's Bill called Cardiac Risk in the Young (Screening), and there was a debate at Westminster Hall. 

There have been nationwide Test My Heart Tour 09 screenings in May and June, backed by Philips, where young people can have free ECG (electro cardiogram) or Echo (ultrasound) scans to check their hearts. 

The final screenings, sponsored by Claire and Paul, are at Brentford Football Club, Griffin Park, Brentford, today until Monday (June 26-29). 

To book a slot at the event, visit www.c-r-y.org.uk

Terrifying toll of 12 heart deaths a week

A staggering 12 healthy young people die each week of an undiagnosed heart ailment. 

Unexplained cardiac death in young people aged 35 and under usually involves thickening or abnormal structure of the heart muscles and irregularities of the electrical impulses that upset the natural rhythm of the heart. 

The majority of these deaths are due to inherited disorders. 

Sport in itself does not lead to cardiac arrest but can trigger a sudden death by aggravating an undetected abnormality. 

If there has been a young death in the family, they are entitled to be screened on the NHS.  Once cardiac conditions are discovered much can be done to prevent complications and sudden death.