Jimmy and Rosalynn Carter: an enduring love story

ATLANTA — It’s a marriage that would span nearly eight decades.

Growing up close by in their hometown of Plains, Jimmy and Rosalynn Carter have known each for most of their lives.

A then-Rosalynn Smith was close friends with Jimmy’s younger sister Ruth.

“I spent a lotta time at that house, but he was always off at school,” Rosalynn Carter told ABC News. “He was so good to Ruth. He would write her letters, and she talked about him all the time. And she had his photograph on the wall in her bedroom. And I literally did fall in love with that photograph.”

[PHOTOS: Jimmy and Rosalynn Carter through the years]

It was that connection that would eventually bring the two of them together to start what would turn out to be the longest-married presidential couple in American history.

They began dating in 1945 while Jimmy Carter was home from the U.S. Naval Academy in Annapolis, Maryland. After their first date, Jimmy Carter told his mother that Rosalynn was the woman he was going to marry.

But Rosalynn didn’t accept his proposal at first. She said no because she told Jimmy that she wanted to graduate from college first, as she had promised her father on his deathbed a few years earlier.

“But he was persistent,” she said.

The couple would eventually exchange vows on July 7, 1946, in their hometown of Plains.

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Throughout their marriage, they would go from their family home to the Georgia Governor’s Mansion and eventually, the White House.

On his 75th birthday in 1999, Jimmy Carter said the most important decision he ever made in his life was “marrying Rosalynn.”

“Rose did say, ‘OK,’ finally, and staying with me all this long has been the most wonderful thing in my life,” Jimmy Carter said. “It’s a full partnership.”

“My biggest secret is to marry the right person if you want to have a long-lasting marriage,” Rosalynn Carter said.

Mrs. Carter said finding common interests was important to the two of them.

“Jimmy and I are always looking for things to do together.” Still, she emphasized a caveat: “Each (person) should have some space. That’s really important.”

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President Carter said they also make an effort to “share as much as we possibly can,” from bird watching to skiing to, especially, fly fishing, which they have done in over a dozen countries, he said.

The two read the Bible together each night.

“We’ve done that for 60 years, probably,” the president told ABC News. “When I’m overseas and Rose is at home, we know we’re reading the same biblical text, and even though we’re separated physically, it makes us think about the same scripture and admonition from God, direction from God before we go to sleep. “So it helps a lot.”

The Carters said they also try not to go to bed angry.

When the COVID-19 pandemic hit, the couple said they barely left their home. While many couples found that to put a strain on their relationships, the Carters said it actually brought them closer together.

[READ: Jimmy and Rosalynn Carter now the longest-married presidential couple]

“Before that, we had not been together all that much -- ordinary family travel and so forth,” Jimmy Carter said.

“It was just Jimmy and me,” Rosalynn Carter said. “And it was really wonderful.”

The Carters said as the years went on, their love for each other just grew stronger.

“For (77) years of marriage we’ve always gone deeper in our love for one another,” the president said. “I think that’s a kind of extraordinary thing. Doesn’t happen to very many couples, but it certainly happened to us.”

ABC News contributed to this article.