Angelina walked out on Brad after discovering a shocking secret — he had a baby with ANOTHER woman!

A fuming Angelina Jolie stormed out after a huge blowup with Brad Pitt when she learned the bombshell news that he had tried to have a baby with another woman — his ex-wife Jennifer Aniston! According to Star, the drama unfolded after a report from the New York Times Magazine revealed that Jen’s close friend, Sue Mengers, advised the actress to request a sample of his sperm for future use after their big breakup!

A shocked and angry Angelina accused Brad of scheming with Jen behind her back, but he adamantly denied the claim. He apologized, but a seething Angelina demanded to know everything, an insider told Star. That’s when the truth came out: Brad and Jen tried to have a baby, but she miscarried.

“He had never told Angie this before,” the insider revealed and added that the 36-year-old felt “betrayed.”

“She had assumed all along that she was the only woman Brad had ever impregnated. Now Angie is questioning everything, including whether she can ever trust Brad again.”

Betrayed and shaken, she walked out and left Brad with their six young children — Maddox, 10, Pax, 8, Zahara, 6, Shiloh, 5 and twins Knox and Vivienne, 3. “Angie started driving to the airport but stopped because she couldn’t bring herself to leave the kids,” the insider said. “She didn’t want to abandon them.”

Although Angelina was surprised by the news, a report in July 2004 revealed that the couple had endured a heartbreaking miscarriage. “It’s a very sore spot for Brad and Jen,” a different source explained. “Neither has talked about it with another person, until now.”

Brad and Jen broke things off in 2005, but their marriage is still a sore spot for Angelina. “Brad doesn’t tell Angie everything, especially when it comes to Jen,” the source explained. “The mention of Jen makes Angie completely irrational. But he never imagined this would infuriate Angie to the extent that it has. Now it could spell the end of them forever.”