Maureen Dunn, the co-founder of the National League of Families of POWs and MIAs, died on Friday, at the age of 72.

On Feb. 14, 1968, Captain Joseph Patrick Dunn's unarmed Navy jet was shot down while flying over the South China Sea. His wife, Maureen, was 27, and their only child, Joe Jr., was 19 months old. Maureen did not become a widow at first, instead she became the wife of a Navy pilot who was declared "missing in action."

Maureen never accepted those words, and instead transformed her personal quest for answers into a national movement that forced the government into a full accounting of all our POWs and MIAs. Her relentless efforts to find out what happened to her husband was a catalyst that prompted McCain and John Kerry’s historic trip to North Vietnam for an accounting of the MIA situation.

A decade earlier, Maureen had laid the groundwork for that trip with her tireless lobbying of Richard Nixon on the eve of his maiden voyage to China.

In 2005, the government finally dedicated a headstone to her husband at Arlington National Cemetery.

Maureen also dedicated herself to the Achilles Project,  which transported soldier athletes who’d lost limbs in Iraq and Afghanistan from Walter Reed Medical Center in Washington, D.C., to Boston to compete in the marathon.

"When it wasn’t fashionable to be talking about the Vietnam War, or all the soldiers and fliers who were declared missing, Maureen was the lone voice out there,” said Maureen's friend Tom Lyons, speaking to the Boston Herald.

On Sept. 13, 1981, Lyons and more than 200 Southie vets who served in Vietnam, consecrated the country’s first Vietnam memorial in honor of the 25 local sons who did not return. Maureen was one the few guests Lyons asked to speak at the dedication.

“We had always been on these similar tracks of trying to remember those who served and sacrificed,” Lyons said. “That’s why I felt it was so important to have Maureen join us all those years ago. We were asking people not to forget our friends. She was that other voice in the wilderness so to speak, only those she was advocating for hadn’t even been found.”