Photo:Scott Cunningham/Getty

Former president Jimmy Carter prior to the game between the Atlanta Falcons and the Cincinnati Bengals at Mercedes-Benz Stadium on September 30, 2018 in Atlanta, Georgia.

Scott Cunningham/Getty

Earlier this year, the Carter family hadn’t foreseen getting to celebrate PresidentJimmy Carter’s 99th birthday alongside him, according to his grandson Jason Carter. But after seven months in hospice care, the 39th president has nearly arrived at the milestone occasion — and wheels are in motion to ensure that it’s his most meaningful birthday yet.

“These last several months have been surprising for all of us,” says Jason, chairman of the Carter Center, “but it’s been a real blessing.” One of those blessings, he tells PEOPLE, has been watching President Carter receive countless messages of love and admiration since revealing hisdecision to terminate medical interventionin February.

Recognizing the unique opportunity that Jason’s grandparents have had to watch their legacy take form — his grandmother, 96-year-oldRosalynn Carter, wasdiagnosed with dementiain May and has received her own outpouring of support — helped inspire the Carter Center’s vision for the former president’s birthday, which falls on Sunday, Oct. 1.

“What we wanted to do was find a way for all of these people [whose lives my grandfather has impacted] to weigh in,” Jason says.

Submissions will ultimately be shared with the Carter family and compiled into a large digital mosaic that demonstrates the magnitude of people who comprise President Carter’s legacy.

Jimmy Carter 99.Jimmy Carter Library & Museum

A mosaic of Jimmy Carter celebrating his 99th birthday

Jimmy Carter Library & Museum

“When you think about his legacy, it is this legacy of all of these individual personal stories that he has helped to define,” Jason explains of the symbolism behind the mosaic. “We thought it was a really appropriate gift, and we’re just thrilled that we get to give it to him.”

In a statement, Carter Center CEO Paige Alexander said, “President Carter has dedicated his life to making the world a better place, and we wanted to give everyone the opportunity to send him love and to thank him for all he has done."

The Carter Center also created an early video tribute to the former president, highlighting many of his career accomplishments.

President Carter has enjoyed the longest post-White House life, and he and Rosalynn have the longest-lasting presidential marriage —77 yearsand strong. He has broken his own record multiple times in recent years as thelongest-living U.S. president, and will do it again on Oct. 1 when he becomes the only commander-in-chief to reach 99.

“President Carter has helped and inspired millions around the globe,” Alexander said, “and we want to celebrate his life, legacy, and this important milestone.”

source: people.com