"This is really what I should do. Why would I do anything else," said 37-year-old Isla Garraway.
Garraway has dedicated her life to finding a cure for prostate cancer — the fatal disease that struck her father when he was just 61 years old.
"I don't know anyone who loved and appreciated and lived life more than he did," she said.
But what makes her story extraordinary, CBS News correspondent Kelly Wallace reports, is that she wasn't alone. Her 39-year-old brother Levi, also with a Ph.D. in medicine and science, made the same decision.
"It was something where I felt like 'this is why I am here' in a sense," Levi Garraway said. "This is why I'm getting up in the morning."
Levi and Isla were stunned when they learned their beloved dad — an Ohio State University professor and biologist — was diagnosed with prostate cancer.
"At first, I couldn't quite believe that could possibly be true," Levi Garraway said.
And he was a bit reluctant.
"Like many men, he felt that if 'I feel fine, there's no reason; if it's not broken, why go and seek a fix,'" Isla Garraway said.
Four years after the diagnosis, Michael Garraway died at the age of 65. That was eight years ago.
"We hope that others will encourage their fathers to get tested and checked," Isla said.
Like her father, Isla is a scientist. She runs her own lab at UCLA's Jonsson Comprehensive Care Center. She's also a surgeon.
Men 50 or older should be getting annual checkups, said the Garraways.
"Like us, many people out there have great fathers and the gift that can be given to them, one of the major gifts, is to keep them healthy, to keep them around for as long as possible," Levi Garraway said.
Although Isla said it's sometimes hard to get her brother on the phone nowadays, when the siblings connect, they often talk shop.
"The other stuff is kind of secondary to what's going on, you know, in the lab for us," Isla Garraway said.
"We're nerds," her brother said.
Make that two of the leading prostate cancer researchers in the country.
Last year Levi led a team at Boston's Dana-Farber Cancer Clinic that made discovery which could lead to a more targeted treatment.
"Those 'eureka' moments — when you get those, you forget about all those nights and weekends in front of the test tubes," Levi said.
They got their love of science from their dad — and their lifelong mission as well.
"He always hoped that he would live to help others fighting the disease," Isla Garraway said. "His hope and dream of inspiring others lives on through myself and my brother."
For more information visit the Prostate Cancer Foundation.
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