Since her 21st birthday sucked, Rihanna‘s new boyfriend “friend” Matt Kemp reportedly surprised the singer Saturday past (Feb 20) with a big party for her 22nd birthday in Phoenix, Arizona. Sources say the “Rude Boy” singer was shocked because she was only expecting a small, intimate get-together with a few friends.

Matt had been planning the shindig, which was attended by about 40 people, for about a month, and it was complete with champagne, a live chef … and a midget stripper. Yes, a little person gave Rihanna a strip tease! In addition, the LA Dodger gave his new girlfriend a custom diamond necklace. Nice!

There were flowers, Sprinkles cupcakes, tiki torches in the pool, engraved bottles of Ace of Spades champagne and Johnny Walker Blue, as well as a Jamaican chef who whipped up lots of appetizers for the crowd. Around 40 people showed up, including both Rihanna’s friends and some of Kemp’s baseball pals.

At one point, a little person billed as  Bridgette the Midget entered and danced around Rihanna to the strains of “So Hard.” Kemp brought out a cake decorated with the songstress’s various tattoos, while everyone sang “Happy Birthday.”

“It was so sweet, and she was really surprised,” the source said. “She looked just beautiful.” Kemp didn’t stop his surprises with the singer’s party, however. According to the source, he gave the birthday girl a custom diamond necklace.

Although the couple has played coy about their budding relationship, they reportedly spent the entire weekend together, first going out on Friday night with a group of 30 on a party bus to new Arizona nightclub Revolver, and then ending the weekend with a group brunch on Sunday.

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