Olsen and boyfriend Justin Bartha stay connected during a romantic Parisian stroll. Plus: Britney Spears, Lindsay Lohan, Justin Timberlake and more

PIECE OF CAKE

Surprise! Lindsay Lohan is feted with a birthday cake Saturday at the Wet Republic pool in the MGM Grand Hotel & Casino in Las Vegas. The actress, who turns 23 on July 2, was in Sin City to promote her Sevin Nyne tanning mist.