Bradley Cooper Talks About The Fake Baby In 'American Sniper'

"I couldn't believe that we were working with the plastic baby."

Bradley Cooper was nominated for an Oscar for his much-talked about performance as Chris Kyle in "American Sniper." But there's one thing people just can't stop talking about in the movie -- the fake baby used as a prop.  

Cooper visited "The Ellen Show" on Monday and discussed the fake baby gaffe with the host.

"I literally, I couldn't believe it," said Cooper, who wiggled the fake baby's arm at one point during a scene to make it look more real. "I couldn't believe that we were working with the plastic baby. I was just like, 'This is nuts.'" 

In between laughs, Cooper continued, "Eat your heart out, 'Muppets."

Watch Cooper talk about the experience more in the clip: 

Sienna Miller, Cooper's co-star in the movie, was on "Ellen" last week and also talked about the fake baby. 

"It looked like something from 'Alien,'" said Miller. 

Correction: A previous version of this post said that Bradley Cooper played Chris Kelly in "American Sniper." He played Chris Kyle. 

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