Britney Spears is officially thirtysomething. Can you believe it?

The X-Factor judge and pop princess turned 31 on Sunday, December 2. Her fiancé, Jason Trawick, tweeted to fans, "Send in ur bday wishes for B on Instagram w/ #HappyBirthdayBritney. We're printing them out and making a flip book to give her as a present." Cute! After that, he tweeted, “I found the perfect card for her!” linking to this photo of a “pretty princess” birthday card for a little girl.

Yep, even at 31 — once a pink-loving princess, always a pink-loving princess. Happy b-day, Brit!

Source: @jasontrawick

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