Joe Stops to Pick Flower for Jill Biden on Their Way to Ga. Rally and to Visit Jimmy and Rosalynn Carter

President Joe Biden and wife First Lady Dr. Jill Biden marked their 100 days in office on Thursday with a trip to a rally in Georgia — as well as stop over to visit with Jimmy and Rosalynn Carter.

On Thursday afternoon, the Bidens, who are set to attend a drive-in rally in the Atlanta area on Thursday night, first visited the Carters' hometown of Plains.

While en route to Georgia that morning, the president shared a brief moment with his wife, picking her a dandelion before they boarded Marine One.

The Carters and the Bidens have a relationship stretching back years and former President Carter has regularly received visits in Plains from Democratic politicians.

In a video message that will play before this weekend's world premiere of Carterland, a new film about the former president, Biden also reflected on their years-long bond.

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Sarah Silbiger/Getty President Joe Biden (right) picks a dandelion for First Lady Dr. Jill Biden as they walk to Marine One on the Ellipse near the White House on Thursday.

Sarah Silbiger/Getty President Joe Biden (right) picks a dandelion for First Lady Dr. Jill Biden as they walk to Marine One on the Ellipse near the White House on Thursday.

"Mr. President, I'll never forget March 25, 1976. That was the day I traveled to Wisconsin and became the first United States senator, the first elected official outside of Georgia, to endorse you, Gov. Jimmy Carter, for president of the United States," Biden says at the start of the video. "All those years ago, Gov. Carter proved me right and in the years since, President Carter did a lot more than that. He showed us throughout his entire life what it means to be a public servant, with an emphasis on the word servant."

The Carters went on to return the favor decades later, endorsing Biden during last year's campaign and appearing by voiceover at the Democratic National Convention.

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BRENDAN SMIALOWSKI/getty Former First Lady Rosalynn Carter (center) walks President Joe Biden (right) and First Lady Dr. Jill Biden out after they after visited her and former President Jimmy Carter on Thursday in Plains, Georgia.

Michael Tran/FilmMagic Left: former President Jimmy Carter and former First Lady Rosalynn Carter in 2015

Biden also shared a few words about Carter's friend and vice president, Walter Mondale, who died this month at the age of 93.

"Of course there's another partnership on our minds right now, and that's the partnership you and your vice president, our friend Walter Mondale had," Biden said in the video message, noting that Mondale was one of the first people he called after Barack Obama asked to consider joining his presidential ticket.

"I miss him. We're all going to miss him," Biden said.

Although the Carters were not present for Biden's inauguration in January, they sent well-wishes ahead of time.

"Mr. President, the night before I put my hand on the family Bible and swore the oath of office, you called Jill and me to wish us well and tell us that you would be there in spirit," Biden said in his video message. "President and Mrs. Carter I want to thank you for your friendship, your leadership. For showing all of us what it means to be an American. Simply put, we love you and may God bless you both."

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The Carters, who have remained dedicated to their humanitarian work over the years, celebrated 74 years of marriage in 2020, making them the longest-married presidential couple. President Carter is also the oldest-ever living former commander-in-chief.

"It's hard to live until you're 95 years old," he told PEOPLE in 2019, crediting his wife as the source for his energy. "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."