Her styling tricks totally kept her baby news a secret! Megan Fox is pregnant and expecting her third child, but prior to her baby bump’s debut at CinemaCon in Las Vegas on Monday, April 11, the Teenage Mutant Ninja Turtles actress had been expertly concealing her growing belly.

Fox, 29, and her estranged husband, Brian Austin Green, 42, are parents of sons Noah, 3, and Bodhi, 2, so the actress has some experience with dressing her burgeoning belly. The unexpected red carpet reveal has fans speculating whether Green is the father, since Fox filed for divorce last August after five years of marriage. The actress hasn’t confirmed who the father is, but joked today about who the dad isn’t. “#notthefather,” she wrote alongside a collage of photos of herself with her former costars costars Shia LaBeouf, Will Arnett and Jake Johnson.

Before she was ready to announce she’s expecting, the New Girl star most recently hid her bump at WonderCon in L.A. with a slimming black jacket and a flowy drawstring top on March 25.

A few days earlier, the former couple were spotted enjoying a meal together at Granville Café in L.A., where the model looked casual in an oversize raincoat and sneakers, and hugged a bag close to her stomach.

Back in early March, the parents reunited again for lunch at Sweet Butter Kitchen in L.A.'s Sherman Oaks. Fox sported a loose-fitting tee and tied a plaid shirt around her waist, and she held two drinks and an iPhone in front of her baby bump.

On another lunch outing in late February, the Transformers star used a conveniently placed purse with tons of fringe and a roomy tank to cover up any signs of a growing belly.

On February 19, the actress disguised her barely there bump by wearing a military-style jacket and carrying her latest reading material.

Tell Us: Which of her bump-concealing outfits was your favorite?

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