Olivia Wilde, Jason Sudeikis

Olivia Wilde and Jason Sudeikis welcomed their first child, a baby boy named Otis Alexander, last Sunday.

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Wilde, 30, broke the news via Twitter Wednesday, posting a picture of herself and Otis with the caption: "Ladies and gentlemen, Otis Alexander Sudeikis has LEFT the building! (I'm the building)."

Wilde and Sudeikis, 38, got engaged in January 2013 and announced last October that she was pregnant. Last December, Wilde told Jay Leno the pregnancy advice her mother shared with her. Watch the interview here.