Angelina Jolie's Plot to Steal Jennifer Aniston's Baby Joy

Whatever else one thinks of Angelina Jolie, nobody doubts her maternal instinct — all you have to do is watch her tend to her flock of six children. And while she and Brad Pitt typically dodge the question of whether they'll add to the brood, the World's Most Glamorous Couple has dropped some heavy hints of late.

"I don't know that we're finished having kids," Brad said in November. And last month, Angie revealed, "I could end up pregnant."

Apparently, they're not toying with us. "Brad and Angelina have been talking about having one more biological child for well over a year, but Angelina's always resisted due to work commitments," an insider tells OK!. "Now that she's getting a bit older (36), the pressure's on."

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Ah, but the biological clock isn't the only thing lighting a fire with Angelina. The Oscar-winner is acutely aware that Brad's ex-wife, Jennifer Aniston, is determined to have a child with her beau, Justin Theroux. And as the source notes, Angelina is fiercly competitive with Jen — not only because of Brad, but also over the romantic comedy queen's massive, generally positive press coverage.

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"For instance, Angelina was furious when a magazine recently voted Jen the hottest woman of all time — while she came in at number 10," the insider says. "Don't get me wrong, Angie's having a child because she wants one, but part of her can't wait to steal Jen's thunder. She knows a Brangelina baby would be the best revenge of all. It's just an added bonus."