Brad Pitt's Obsession With 'Hunger Games' Beauty Jennifer Lawrence

It took a three-day, across-the-globe separation from Brad Pitt for Angelina Jolie to "let off steam," says an insider, over his growing infatuation with The Hunger Games star Jennifer Lawrence. And the blow-up began in earnest after Angie learned Brad was texting the stunningly seductive 21-year-old actress.

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"Brad hasn't stopped talking about how gorgeous, poised and talented Jennifer is," the insider tells Star, and adds that Brad is "determined to find a project to collaborate on" with Jennifer through his company, Plan B Entertainment." "He was already a huge fan of her work in the 2010 film Winter's Bone, which earned her a Best Actress Oscar nomination. And once he saw an advance screening of The Hunger Games, he just flipped."

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But Angie isn't thrilled about the 48-year-old Brad's obsession, says the insider. "She warned him to act his age and stop drooling over a girl young enough to be his daughter. She even hit him with the jab, 'Which Jennifer are you talking about?' — a reference to his ex-wife, Jennifer Aniston — when he wouldn't stop gushing."