One of the contestants on the upcoming season of 'X Factor' U.K. may have a famous sibling. 

The Mirror reports that actor Robert Pattinson's older sister Lizzy recently sang at a closed-door audition for the show in London.  Sources tell the site that she impressed judges Simon Cowell, Cheryl Cole, Mel B and Louis Walsh, and could be appearing on the premiere later this month. 

In an interview with Grazia promoting his film The Rover, Robert confirmed that his sister did audition for the show, which will air on the AXS TV channel in the U.S. for the first time this season.  The actor says he's "ridiculously proud" of her and that he "can't believe" she had the courage to sing for the panel. 

Sources say Lizzy kept her relation to Robert quiet from producers, and is hoping to move forward on the show based on her own talents.  

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