Katy Perry's birthday was on October 25, and she celebrated it with an unforgettable experience: having lunch with first lady Michelle Obama .

Katy tweeted a picture of herself posing with Mrs. Obama, adding the comment, "NOW my bday is complete!"  The previous night, Katy had performed at a fundraiser for President Obama in Las Vegas, where her grandmother lives.  Katy later tweeted , "Tonight was a great night! The PRESIDENT gave grandma and I unforgettable shout outs & now I am officially 28! Best. birthday. ever."

Also on Thursday, Katy sent a message to all her fans, saying, "Thank you all for making me feel so special today," she tweeted. "I'm overwhelmed with all the love that I might have a small happy cry now. So blessed."

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