The diva shows off her two-piece during a yachting expedition. Plus: Mandy & DJ AM, Gwen & Gavin and more

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GRILLIN' & CHILLIN'

Ashlee Simpson cozies up to beau Pete Wentz at the 10 Cane Rum Dinner – a barbeque at Stereo House in Watermill, N.Y. The Fall Out Boy bassist hosted the evening's festivities before taking off (with Simpson) to nearby nightclub Dune, where he deejayed.