The mystery man responsible for Megan Fox's third pregnancy has been revealed. People magazine has confirmed that the actress' ex-husband, Brian Austin Green is the baby daddy to her third child.

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The couple who have been separated since August, were spotted in Los Angeles on Tuesday, April 12 and seem to be in good spirit. The mag reports that the pair is working on their marriage since she showed up at CinemaCon in Las Vegas on Monday, April 11 with a surprise baby bump.

A source confirmed to the mag that Austin Green is "of course" the father and that the pair "never stopped loving each other and they will never stop being devoted parents to their boys."

Fox, 29, showed off her baby bump in a colorful print maxi dress while her estranged husband Austin Green wore all black for their day trip out.

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While they may have not been holding hands, the couple appeared to be in good spirits as they walked side by side together. However, TMZ claims Megan has revealed the divorce is still on.

According to Wendy Williams, the couple still live together … So we can now understand why he's the baby daddy!