TMZ: We've learned Mel Gibson's girlfriend, Oksana Grigorieva, is pregnant with his child.

Our sources say Gibson has already told his estranged wife, Robyn, and their children about the news. We're told Oksana is in her second trimester.

Robyn filed for divorce on April 13.

By the way, Oksana is living in a house Mel got for her. And guess what else? Until recently, Oksana was living in a house purchased by songwriter/producer David Foster, with whom she also had a relationship.

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