Heather Murphy, 42, has been diagnosed with cardiomyopathy, which killed her father.
Her teenage daughters Hannah, 17, Chloe, 15, and Katie, 14 are waiting for the results of tests for the condition, which is a disease of the heart muscle.
Heather's father Kenny Jenkins, a former professional footballer who played for Dumbarton and Albion Rovers, died aged 62 after waiting months for a heart transplant.
Mr Jenkins' father, George, a goalkeeper with Rangers in the 1930s, is also thought to have had the same condition.
Heather's aunt, who lives in Australia, has also been diagnosed with cardiomyopathy, which is a disease of the heart muscle that can cause sudden death.
Heather and husband Stephen, 45, are facing an anxious wait to find out if their daughters are affected. There is a 50% chance a child will inherit the condition from a parent.
The Murphys, of Paisley, have backed our campaign, launched this week, to persuade the Scottish Government to launch an 'opt out' system of organ donation. where everyone is automatically placed on the donor register.
It would mean that, unless people opted out or relatives objected, hospitals would be allowed to use their organs for transplants.
Support for a change in the law is supported by the British Medical Association and major charities, including The British Heart Foundation, Kidney Research UK, Diabetes UK and the Cystic Fibrosis Trust. They believe it is the best way to address a national shortage of donors.
The Murphys, who are all donors, believe Heather's dad might have survived if a heart transplant had been possible at an earlier stage.
Cardiomyopathy is the main cause of heart transplant surgery.
Cardiologists have warned of "critical" shortages of donor hearts and the demand is likely to increase because existing levels of obesity and Type 2 diabetes are expected to lead to an increase in the number of people with heart failure requiring transplants in the future.
Mrs Murphy said: "I think opting out is a much better way. People can say if they don't want to do it. They just have to say they put in that bit of effort to say no.
"They didn't discover my dad had a heart condition until it had caused problems.
"He was put on a heart pump and the debate started whether he was fit enough for a transplant.
"Then he had to convince them about giving him a transplant and the impact it would make on his life. It is hard when they say, 'We can't waste a heart'."
Stephen Murphy said: "We are all Christians and think, 'I don't want to pray for a heart because I'm praying for someone to die'."
Sadly, Mr Jenkins' condition deteriorated before they could find a donor heart and the family gave doctors at the Golden Jubilee Hospital, Clydebank, permission to remove his heart pump. He died on November 13, 2009.
Six weeks after her father's death came the further devastating news that Mrs Murphy, who owns a nursery, was showing early signs of the condition.
She said: "When they tested me they said my heart was slightly too big.
"They have put me on treatment, which I hope will mean it will not deteriorate. They told me I probably will not have problems until I am older."
Cardiomyopathy affects one in 500 people of all ages, including babies. It is not curable but is treatable with drugs and, sometimes, surgery, pacemakers and internal defibrillators. In most cases, treatment allows sufferers to lead a long and full life.
Problems arise if it is undetected when carriers are at risk of arrhythmia or sudden cardiac death or both.
Mr and Mrs Murphy's three daughters are waiting for the results of genetic testing.
Mr Murphy said: "We pray every day about that."
He and oldest daughter Hannah, 17, will take part in a charity cycle from Vietnam to Cambodia from November 5-14 to raise funds for the British Heart Foundation's Mending Broken Hearts Appeal.
They are hoping to raise £10,000 and are more than halfway to their target.
Ben McKendrick, of the British Heart Foundation Scotland, said: "At the moment, a heart transplant is the only effective treatment available for end stage heart failure patients but, worryingly, the rate of heart donations has slumped over the past two decades.
"The reality is nine out of 10 of us want to donate, but about 25% join the donor register. "We would like to see opting out legislation across the whole of the UK.
"I would like to congratulate the Evening Times for raising the important issue of organ donation."
l If you wish to sponsor Stephen and Hannah see: http://original.justgiving.com/stephenandhannah
THE Evening Times has launched a campaign to persuade the Scottish Government to create
an opting out system of organ donation, where everyone is automatically placed on the donor register. It would mean that, unless people 'opt out', hospitals can use their organs for transplants after they die