Did You Spot Conan O'Brien's Sister in The Fighter?

Monday December 20, 2010 11:45 AM EST

Conan and Kate O'Brien

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In The Fighter, Mark Wahlberg and Christian Bale claim the most screen time, but there's no denying their slew of sisters' scene-stealing abilities.

What you might not have realized is that one of the Eklund women has a famous brother in real life, too. Kate O'Brien, sister to late night TV host Conan O'Brien, plays Phyllis "Beaver" Eklund in her acting debut.

"I work at a school and someone said, 'They're casting [The Fighter], you should go down, you look Irish Catholic,' " Kate O'Brien told PEOPLE. "I'm one of six, so it wasn't that hard for me to look like I might have more siblings [in the movie]."

• Reporting by ANNE DRISCOLL

Kate O'Brien (second from left) in The Fighter

Paramount Pictures

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