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It's the baby bump the whole world has been waiting for: Jennifer Aniston's!

Alas, the 43-year-old "Wanderlust" star -- set to wed beau Justin Theroux -- isn't with child just yet. But Aniston straps on a convincing pregnant belly in a hilarious new viral video for smartwater.

PHOTOS: Jen shows off bikini bod on vacation with fiance Justin Theroux

With cameos by Ryan Seacrest and Jimmy Kimmel, the video reveals so-called "security tapes" starring the beloved star (and smartwater spokeswoman) -- who crashes a sports car, fills her swimming pool with smart water and sports a bowling-ball sized baby bump.

PHOTOS: Jen's hair history

Another pseudo-shocker caught by security cameras? Aniston's world-famous hair is a wig!

See a "pregnant" Jennifer Aniston reveal her "real" hair and much more in this clip!

This article originally appeared on Usmagazine.com: See Jennifer Aniston With a Baby Bump!

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