Playboy model twins Karissa and Kristina Shannon got the royal treatment Saturday at Sugar Factory at the Miracle Mile Shops at Planet Hollywood Hotel and Casino for their 21st birthday. The "Girls Next Door" stars (Kristina in the red dress, Karissa in pink) sucked on the treat shop's signature "Couture Pops" and shared birthday cakes and red velvet cupcakes. Karissa, as usual, had her boyfriend Sam Jones III in tow.

But one shot that Karissa and Sam posed for has us wondering if she might be pregnant. Jones has his hand on her tummy while she holds up a peculiarly small t-shirt.

We hope she isn't though, because the pair partied into the night Friday in New York City with lots of champagne and vodka.

After their trip to the confectionery, the three were spotted at the Cabo Wabo Cantina where Karissa and Kristina had giant frozen drinks.

Karissa has been in the headlines alot recently as a sex tape featuring her and Jones is on the verge of being released by porn giant Vivid Entertainment.

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