The first lady gets an early birthday present, but what is President Obama planning?

By Sandra Sobieraj Westfall
January 17, 2014 11:00 AM

She’s 50 and fabulous – and has the ID card to prove it!

First Lady Michelle Obama turned the big 5-0 on Friday, and showed off one of her first birthday gifts, courtesy of the American Association of Retired Persons: a free membership card.

“Excited to join Barack in the 50+ club today check out my @AARP card!” she wrote on Twitter next to a photo of herself grinning and showing off the card. Some 50-year-olds dread receiving it, but not Michelle!

“I don t feel that much differently than I did when I was younger,” Mrs. Obama told PEOPLE in advance of her big milestone. “What I hear is that age is a number, it s a state of mind.”

As for what President Obama might be wrapping in ribbon for the birthday girl today, “That’s top-secret,” he tells PEOPLE. “Not even the NSA knows that.”

For more of our interview with the First Lady – including her thoughts on Botox, menopause and becoming a grandma – pick up the latest issue of PEOPLE, on newsstands now.

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