Former President Jimmy Carter was the longest living president in U.S. history, and credited his longevity in part to marrying the best spouse, his wife, Rosalynn Carter.

James Earl Carter, Jr., served as the 39th U.S. president. Carter died at the age of 100 on Dec. 29, 2024. His funeral will be held on Thursday, Jan. 9, in Washington D.C. and the date has been declared a day of mourning by President Joe Biden.

Carter's wife, Rosalynn Carter, died in November 2023 at the age of 96. The pair were married for 77 years and had four children and a total of 22 grandchildren and great-grandchildren.

What was the secret to the Carters living a long and happy life? Each other.

When asked what he thought leads to a long, happy life, Carter told People Magazine: "I think the best explanation for that is to marry the best spouse: someone who will take care of you and engage and do things to challenge you and keep you alive and interested in life."

The former president and first lady actually weren't super focused on longevity, he told People; they spent most of their time searching for opportunities to serve their community and pour into each other.

Their love story began in their hometown of Plains, Georgia, Mr. Carter told The Washington Post. After meeting at Plains United Methodist Church, he asked Rosalynn on a date to the movies, and told his mom that he was going to marry her the next morning, he said in his interview with The Post.

During his presidency, Rosalynn sat in on his Cabinet meetings, according to Rolling Stone.

The couple also founded The Carter Center, a nongovernmental organization devoted to improving lives, in 1982. The center has built thousands of homes in over 10 countries alongside Habitat for Humanity.

"What Rosalynn and I wanted to do was fill vacuums, resolve problems others weren't able or willing to do," Carter told Rolling Stone.

Later in life, the Carters enjoyed quality time together through activities like tennis, downhill skiing and bird-watching: "Rosa and I have seen about 1,300 different species of bird," he said in his interview with People.

After his presidency, the couple moved back to their hometown and bought amodest $167,000 home.

"Now when we have a quiet moment, like a birthday or something, we like to stay at home, just by ourselves," he added, "And enjoy a quiet day in our own house without any visitors and with minimum phone calls and emails coming in."

They even celebrated their 77th wedding anniversary in July 2023 at their Georgia home, making them the longest-married first couple.

The dynamic duo lived in their home until their passing. Carter will be buried on the property next to his wife, Rosalynn, according to PBS News.

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