Reports say that Jennifer Aniston, 45, is sporting a baby bump on the set of her new movie Cake. If she is indeed knocked up, this will be her first child with Justin Theroux, 42.

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 A source close to the couple revealed in the May 12 issue of InTouch Weekly that the couple already knows the sex of their child:

"[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 Wednesday.

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So, it's not too late? A source on the Cake set reveals that Aniston's already showing possible pregnancy symptoms - namely vomiting.

"In early April, Jen called Justin crying from the set. She said she couldn't stop throwing up. So he dropped everything, hopped on his bike, and drove over so he could personally deliver Jen's favorite organic ginger ale to her," the source said.

Despite the nausea, Aniston and Theroux (this would also be his first child) are over the moon.

"[Jen's] telling friends this is a miracle baby. She'd pretty much given up on conceiving naturally," the source shared.

Tags: Jennifer Aniston Justin Theroux pregnant baby bump Cake