Simon Sudman was healthy - all cheeks and, at three months old, almost sleeping through the night.

On Jan. 24, 2005, he never woke from his after-dinner nap.

"We looked over and he was blue and he was gone," recalls his father, Darren Sudman, 42.

This Philadelphia small business consultant and his wife, Phyllis, couldn't accept the initial finding of SIDS and worried about their daughter Sally (now 10) being at risk for whatever killed her baby brother.

"Our doctor said, 'Healthy babies don't just die; you guys should go get your hearts checked,' " says Darren. They did. And they've been getting hearts checked ever since.

Phyllis, now 41, was diagnosed with - and successfully treated for - the previously undetected, hereditary and potentially fatal Long QT Syndrome. She unknowingly passed it to Simon. If left untreated, it could have stopped her heart at any time.

"The screening was so simple," says Darren. "We knew we had to do something to prevent other deaths like Simon's."

In the seven years since the Sudmans founded Simon's Fund, they've raised hundreds of thousands of dollars - through fund-raising events with friends and local businesses - to provide to provide free heart screenings to almost 5,500 children. Forty-nine of those screenings detected potentially fatal heart conditions that were subsequently treated.

"They saved my life," says Melissa Fair, who was 9 years old and on her way to cheerleading practice when a Simon's Fund screening at her local elementary school, turned up a congenital birth defect. She underwent corrective open-heart surgery on Jan. 24, 2008. "That night, I went on Simon's Fund website and gasped," recalls her mom, Lori. It was the third anniversary of Simon's death.

Melissa now makes and sells bracelets and head bands with silver hearts called "heart bands" to raise money for Simon's Fund.

The Sudmans also got Pennsylvania to enact last year a new law requiring that coaches remove student athletes showing signs of risk for Sudden Cardiac Arrest (fainting during exercise, extreme shortness of breath and dizziness among them) until cleared for play by a doctor.

"We don't want to do this forever," says Darren, "just until checking kids' hearts becomes the standard of care."