Everyone knows about some famous celebrity siblings. The Kardashian Klan, Olsen Twins, Jessica and Ashlee Simpson, the Gyllenhaals, and many other sets of siblings have long been a part of Hollywood.

But not every brother or sister is as famous as their family. To prove that point, Glamour and our friends at XUMO got together and created a video of the top 8 sets of half-famous Hollywood twins out there. How many of these people did you even know had a twin (and where have the cute ones been all this time)?

Check it out below, and let us know what you think.

Glamour on XUMO: 8 Celebrities You Didn't Know Had a Twin from XUMO on Myspace.

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