Ha! Forget pregnancy brain; Megan Fox has got jokes. The Teenage Mutant Ninja Turtles star, who is pregnant with her third child, joked about who the father is on Instagram on Tuesday, April 12.

“#notthefather,” the actress, 29, wrote alongside a collage of photos of herself with her former costars Shia LaBeouf (Transformers), Will Arnett (Teenage Mutant Ninja Turtles) and Jake Johnson (New Girl).

Her joke comes after the actress debuted her baby bump at Cinemacon on Monday, April 11. Her unexpected reveal caused fans to speculate as to whether her estranged husband, Brian Austin Greenis the father.

Fox filed for divorce from Green after five years of marriage last August. The two are already the parents of sons Noah, 3, and Bodhi, 2.

As previously reported, they've been amicably coparenting ever since their split and have been seen out together in Los Angeles numerous times.

At the time of their split, a source told Us that things had been “rocky.”

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