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It's a boy!

Megan Fox and hubby Brian Austin Green expanded their brood last month without anyone the wiser. Megan took to Facebook this morning to announce the September 27th birth of a bouncing baby boy.

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"He is healthy, happy, and perfect," writes Fox of newborn son Noah Shannon Green.

"We are humbled to have the opportunity to call ourselves the parents of this beautiful soul and I am forever grateful to God for allowing me to know this kind of boundless, immaculate love," she continues. "Thanks to those of you who wish to send your positive energy and well wishes. May God bless you and your families abundantly."

Noah makes an older brother of Brian's son Kassius, 10, from a previous relationship.

Throughout her pregnancy, Megan stayed characteristically mum. As rumors flew, the Transformers star opted to let her burgeoning bump do the talking during a trip to Hawaii in June.

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Our congrats to the happy couple!