Conan O'Brien may be facing some friendly sibling rivalry as his sister is getting some recognition for her role in 'The Fighter'.

The film boasts an all-star cast including Mark Wahlberg, Christian Bale and Amy Adams, but it is Mark and Christian's sisters in the movie that are being hailed as the scene-stealers of the flick. Conan's sibling Kate O'Brien plays Phyllis "Beaver" Eklund in the Golden Globe-nominated movie.

Amy Adams, who stars as Mark's onscreen girlfriend Charlene Fleming in the movie, shared some scenes with Conan's sister. "[Kate] had a complete blast. She does an amazing job," Conan told Amy when she appeared on his late-night show. "She loved the experience."

One scene in particular, Amy gets into a fight with the slew of sisters, and it gets pretty physical. She said 'The Fighter' director David O. Russell "wanted it to look like we were getting hurt, [and] that's hard to do without getting hurt."

There was hair flying," she described the scene to Conan. "We just went for it. ... I didn't hit anyone in the face."

The film is based on the boxer Micky Ward and his brother Dicky Eklund who have a lot of sisters in real-life, six in the film. Conan said of his movie-making sibling, "I look like her now. She's the famous one."

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