AMBLER, Pa. >> My mother is the second-youngest of 14 children, and her five eldest siblings served overseas in World War II. They were our version of the famed Sullivan brothers, but with a happy ending: All made it home.

Though one brother died in a 1948 car crash, I grew up around the other four, seeing them most every Sunday after church while my grandmother was still living, and at family picnics that inevitably featured volleyball, Aunty Betty’s decadent cakes, and the low roar of two dozen simultaneous conversations.

Regrettably, in all that talk, I never got around to asking my uncles about their wartime service. I’d been meaning to. I just never did.

Now there is only one left to ask, the one who took part in the D-Day invasion on June 6, 1944: Uncle Bert.

Richard “Bert” King is 89 and his memory is failing. I’ve had a growing sense that I’d kick myself if I never got to hear his story, from his lips. Sure, I understood that he might not be able to provide every detail after 70 years. But I came up with a list of questions — and finally, just the other day, I sat down with him to ask them.

Many American families are racing to capture their veterans’ memories before it is too late. Of the 16 million who served, about 1 million World War II veterans remain, and they are dying at a rate of more than 400 per day. There will be fewer than 100,000 a decade from now and none by 2036, the U.S. Department of Veterans Affairs predicts.

My uncles never discussed the war much with their younger siblings, probably out of a sense of modesty and a desire to move on.

That wasn’t unusual. For many years after they returned home, veterans were often reluctant to talk, said Nick Mueller, president and CEO of The National World War II Museum in New Orleans. They wanted to rebuild their lives, and they felt uncomfortable discussing what they’d seen.

“This is such an intensely personal experience with their comrades in arms, battlefield situations, horrific experiences that are almost indescribable to someone who wasn’t there with them,” Mueller said. “They just didn’t want to talk about it because it seemed to trivialize, I believe, their memories of those who didn’t make it back.”

That began to change a couple decades ago as World War II veterans entered their 70s and nostalgia set in. The 50th anniversary of the war, and books like Stephen Ambrose’s “Band of Brothers,” rekindled interest. The National World War II Museum often fields inquiries from families looking for advice on how to take an oral history.

As for my own family, I’d heard snippets over the years. Frank Jr., the eldest, was in the Army band for a time and went on to serve throughout Europe in an artillery unit. Charles was a general’s secretary. Harold served in Africa. Edgar fought in the Battle of the Bulge and got a Purple Heart. And Bert was a radio operator. To this day, he finds himself tapping Morse code on the armrest of his easy chair.

Several 1940s-era documents, some written in his hand, provided important clues as I prepared for our talk. One said he belonged to a D-Day landing party on Omaha Beach that directed naval bombardment of enemy positions. Another said he was subsequently re-assigned to the 274th Armored Field Artillery Battalion. He was honorably discharged as a technician fifth grade on Oct. 20, 1945, according to his separation papers. He had served 943 days.

I met with Uncle Bert and his daughter, Terry Meyer, at his apartment in the Philadelphia suburbs, and he was just as friendly and easygoing as ever.

When I reminded him about the upcoming 70th anniversary of D-Day, he quipped, “Geez, I’m getting old.”

Memories of his wartime service came in fragments but were no less powerful. He told me about dodging German subs on the nausea-inducing voyage to Europe, a trip he called “the worst 10 days of my life.” About the bitter cold of the Battle of the Bulge late in 1944. (“It was brutal. I made a promise to myself that I’m never gonna freeze again.”) About the frozen corpses.

He told me how he once took cover in a doorway and a shell exploded next to him, causing permanent hearing loss.

But his fading memory yielded just a few scraps about the Normandy invasion itself — a vague recollection of entering the water as the Germans fired on a nearby landing craft.

“I wish I could remember. I can’t,” he said. “Maybe it’s a good thing.”

Forty-five minutes after we began, I switched off the camera and thanked Uncle Bert — for the bits and pieces of his role that he shared, for the privilege and awe I felt in hearing them, and for his service so long ago.