They are always up to something, and the Shannon twins were spotted arriving at The Beverly Club in West Hollywood, CA on Thursday night (July 28). Both clad in revealing night-club attire, Kristina and Karissa flashed their ID’s at the front door before heading into the swanky venue

Making a brief trip south of the border, Karissa and Kristina Shannon headed to Cancun, Mexico for the Spring Break 2011 festivities. The Playboy beauties ventured to the popular locale on Thursday (March 10), with Karissa tweeting, “Taking off to Cancun!!!! I’m so ready to party this party tonight is going to be one memorable party no matter how drunk you are!!!!” Once arrived, the ladies – who were joined by Kristina’s beau Sam Jones III – proudly showed off their backsides in the crystal clear waters while also spearheading a raucous party at Daddy O. Having since made their way back to California, it certainly sounds as if Karissa and Kristina didn’t hold back on their celebratory efforts.

Making for quite the reason to celebrate, twin sisters Karissa and Kristina Shannon rang in their shared 21st birthday with a booze-fueled party in New York City on Friday night (October 1). The Playboy beauties – who turned 21 at midnight – first went to dinner at Via De Mille restaurant in SoHo before heading to their very own party at Greenhouse nightclub.

Seemingly unhappy to have sensitive material floating around in the wrong hands, Karissa Shannon is gearing up to take legal action as necessary against Spencer Pratt . According to TMZ, the Playboy beauty has voiced plans to sue the former “Hills” star if her doesn’t return a sex tape including herself hooking up with Heidi Montag . The report contends that Spencer took the video from Karissa – with her lawyer demanding that the property be returned immediately

Showing some serious sisterly love, Karissa and Kristina Shannon were spotted sharing a smooch at the Midsummer Night’s Dream Party on Saturday (August 7). The “Girls Next Door” babes looked lovely as they made nice for the camera as part of Hugh Hefner’s Annual Playboy mansion shindig. As for the upcoming tell-all book about the goings on at the Playboy mansion, former Hef girlfriend/Girl Next Door Kendra Wilkinson says she’s not in support of it and blames one of the Shannon twins for the project

Stepping out for a fancy evening, Jayde Nicole was spotted arriving at Beso restaurant in West Hollywood last night (February 23). The Playboy Playmate was all smiles as she strolled up to Eva Longoria’s uber-popular eatery, sporting a grey sweater with black leggings and grey boots.

Fresh from their move out of the Playboy Mansion, Karissa and Kristina Shannon enjoyed a night out on Wednesday (January 20) in Los Angeles. The 20-year-old twin sisters were spotted outside of the well-known Katsuya restaurant, eating up the paparazzi attention and looking to enjoying their new found freedom

Indulging their collective sweet tooth, the “Girls Next Door” ladies were spotted visiting Millions of Milkshakes in Los Angeles last night (December 14).

Turning everything into a spectacle, Hugh Hefner and his Playboy bunnies were out in sunny Los Angeles, CA yesterday (September 18). The 83-year-old and the Playmates were out selling lemonade and Playboy bottled water in order to raise money for the October 18th LA AIDS walk.