Here’s how to help wish Rosalynn Carter a happy 91st birthday

Many happy returns, Rosalynn Carter!

The former first lady of Georgia and the United States turns 91 on Saturday, and the Jimmy Carter Presidential Library and Museum wants the public to get in on the celebration. The namesake Atlanta instititution has a birthday card visitors can sign.

Rosalynn Carter will mark the day with family and friends, according to Jill Stuckey, a close friend of the Carters' in their lifelong hometown of Plains. It'll likely be a little more, uh, down to earth than her most memorable birthday celebration, which she told the Atlanta Journal-Constitution about in an exclusive 90th birthday interview last year.

That was her 51st birthday, the second one she spent in the White House.

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“My staff gave me a ride in the Goodyear Blimp,” she recalled during the interview, which Jimmy Carter popped into at one point to chat about any advice he’d given her about approaching her milestone day. “They had to draw straws for who would go with me because we couldn’t get everybody in. I had a great birthday!”

Explore >>Related: Jimmy and Rosalynn Carter headed to Canada to help build Habitat houses

Meanwhile, there’s another milestone quickly coming up for the Carters. Every year since 1984, the former president (who’ll be 94 on Oct. 1) and his wife have led ambitious Habitat for Humanity building projects everywhere from Eagle Butte, South Dakota (1994) to Lonavala, India (2006).

Last year, the project headed to Canada, where Jimmy Carter had a self-described "weak moment" when he became dehydrated on the building site and was briefly hospitalized. And his wife of 72 years underwent intestinal surgery back in February.

Explore >>Related: Jimmy Carter describes wife Rosalynn’s surgery

But you can't keep Habitat's most dedicated volunteers down. Come Aug. 27, the couple will be in Mishawaka, Indiana, as the 35th Jimmy and Rosalynn Carter Work Project gets underway for a week of building 22 new affordable homes.

(The Jimmy Carter Presidential Library and Museum is located at 441 Freedom Parkway, Atlanta. The museum, which includes the lobby, is open 9 a.m.-4:45 p.m. Monday-Saturday, noon-4:45 p.m. Sunday. Admission: $8; senior citizens (ages 60 and older), military and students, $6; ages 16 and younger, free.