Jennifer Aniston has apparently defied the odds with her later-in-life pregnancy at 45. This will be the first child for her and fiancé, actor Justin Theroux, 42. The rumor mill is all a-flutter with the speculations that the little bun in the oven is a girl.

For Friends Star It Ain't Too Late At 45

A source told May issue of In Touch Weekly that the couple was definitely expecting.

"[Jen's] a little more than three-and-a-half months along and just found out the baby's sex," the source revealed. "It's incredible news for the two of them. Just a few months ago they were on the brink of splitting," according to HollywoodLife on April 30.

Jennifer Aniston Changes Mind A Million Times About Wedding To Justin Theroux

The actress has been childless for a long time - which fed rumors that Brad Pitt famously left her (for Angelina Jolie) for that reason. While no one really knows the intimate details for their split, a bundle of joy would be a welcome addition for the hard-working actress. She was spotted on the set of her new movie, Cake, where her baby bump has reportedly been seen.

When it comes to her wedding to fiancé Theroux, Aniston - who's obviously been down the aisle before- remains indecisive, as noted in an earlier Enstars report.

"Jen is the most indecisive woman on the planet... She's changed her mind a million times about everything," a source reported.

The source continued, "Jennifer has been dreaming about a fairytale wedding to Justin... But it just keeps eluding her grasp."

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