Teeny tiny bikinis! Exotic beaches! Count down The Hills star's sexiest days in the sun in honor of her birthday
Credit: Ethan Miller/Getty
Updated: Monday Jun 14, 2010 | 06:15 AM EDT
By: Andrea DeSimone
More from PEOPLE
See More News
As these Hollywood hunks prove, they put hard work into their mass appeal
4 of 16
Taking a break from being the bikini babe in the family, Audrina picks a monokini while sister Casey goes for a red-hot two-piece to accent her tattoos for some poolside antics in Las Vegas.
Copyright © 2014 Time Inc. All rights reserved. Reproduction in whole or in part without permission is prohibited.