Bill Krissoff, 61
Reno

On the morning of Dec. 9, 2006, Bill Krissoff was making oatmeal when he heard a knock. Outside stood a chaplain and four Marines: His older son, First Lt. Nathan Krissoff, 25, had been killed by a roadside bomb in Iraq. "The blood drained from my head," says Krissoff, who woke wife Christine. "But I'm a surgeon, so I went into functioning mode. You do what you have to do."

He also did something not required. The orthopedist, with no previous military experience, signed up for a three-year hitch with the Navy Medical Corps Reserves. After he completes training in several months, he hopes to go to a field hospital in Iraq. "I'm honored they'll have me," he says.

Navy Surgeon General Adam Robinson says the honor is theirs: "Dr. Krissoff brings the critical skills and extensive experience that are in such great need." It wasn't easily done. Though fit—the 5'8", 160-lb. Krissoff swims a mile a day—he's 19 years over the Naval-enlistee age limit. Special waivers, granted to a small number of older medical specialists, can take up to a year to get. So after applying, Krissoff pressed his case in August, when he met President George W. Bush at an American Legion convention. "He asked, 'Is there anything the White House can do for you?'" Krissoff recalls. "I said, 'I want to serve.'"

Another authority he had to persuade: Christine, 56, his wife of 29 years and mom to Nathan and son Austin, 24, a Marine stationed in Southern California. "I was teary," she says. "But after losing a child, it's hard to go back to your normal life."

On Nov. 17, wearing service dress blues, Krissoff swore his oath in a ceremony at home. As friends and family raised their glasses, the doctor's thoughts turned to Nathan. "If he had been there, he'd have told me, 'Congratulations,'" he says now, choking back tears as he encircles an invisible shoulder with his right arm. "He'd be proud."

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