Ashley and Mary-Kate Olsen
and Ashley Olsen
, enjoying dinner and dancing together at Lavo, inside the Palazzo Las Vegas. After celebrating a friend's birthday with a meal in the private dining room, the twins headed upstairs to the club, where they snagged a table on the dancefloor. "They danced non-stop with their friends and playfully took photos of each other," says an onlooker, noting that the twins stayed until after 3 a.m. "They loved the music the deejay was spinning."