From the sexy Simpson sisters to the hunky Hemsworth brothers, Hollywood is teeming with gorgeous celebrity siblings.
It begs the question: which star shines brighter? Is Kate Mara more desirable than her little sister Rooney? Does Drew Lachey have an edge over his older brother Nick?
Though most celebrity families appear to be tight-knit, that doesn't mean there isn't a "healthy competition" between most siblings. Case in point: Kate and Pippa Middleton.
PHOTOS: WHO'S THE HOTTER STAR SIBLING?
"Certainly when it comes to looks, like who is the slimmest or better looking, there is a little friendly rivalry," royal watcher Katie Nicholl told Us Weekly in 2011.
Other famous celebrity siblings include Beyonce and Solange Knowles; Owen and Luke Wilson; Emily and Zooey Deschanel; Nick and Joe Jonas; and Paris and Nicky Hilton.
Who do you think is the hotter star sibling? Check out Us Weekly's gallery and cast your vote now.
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