JENKS, Oklahoma - This week would have been her fifth birthday, had she survived the final surgery for her congenital heart defects. Now, the family of a little Jenks girl is helping lead the fight against the world's most common and deadliest birth defect.

The Hilsheimer family started the Lauren Elise Memorial Foundation to help other children going through the same thing, and to make sure treatment is available locally.

For the Hilsheimer family, old photos are as far as they got to see Lauren grow up.

"We sent her home on July 22, 2011," said Kirsten Hilsheimer. "She was 3 years, 1 month and 19 days old."

She and her husband, Mark, knew Lauren was special before she was born. Halfway through the pregnancy, a routine ultrasound led to a diagnosis of six different congenital heart defects. At ten days old, Lauren underwent the first of three major surgeries her tiny body would need to survive.

It went perfectly and she sailed through the second surgery. She thrived through the next three years and wore her scars with pride.

"We always tried to make it a very positive thing," Kirsten said. "She was kind of proud of it, it was her badge of courage. 'That's my badge,' she would say, 'that's my badge!'"

After her final surgery, Lauren's heart stopped on the way to the recovery room. She passed away two days later.

"I don't think many people, unless you've gone through it, understand the depths of the grief associated with losing a child," Mark said.

Their grief turned into determination.

One out of every 100 babies is born with a congenital heart defect. The family started the Lauren Elise Memorial Foundation to promote awareness, research and early diagnosis.

"We continue to fight, not only for her, but the hundreds of thousands of other children who are affected with CHDs," Mark said.

They teamed up with Children's Hospital at Saint Francis. With foundation funds, the hospital has already bought new, state-of-the-art equipment to help the tiniest heart patients and continue Lauren's legacy.

"Although our story did not end the way we wanted it to, I think our foundation can offer other families hope," Kirsten said.

The foundation has its big fundraiser this weekend and will pay for the construction of "Lauren's Heart Room" at Children's Hospital.