A clue: it's not Angelina, and it's not Jamie Lynn. It's not even a woman. it's...

Jason Lee!
Okay, so, he's not actually having the baby - his girlfriend, Ceren Alkac, who is not, to the best of my knowledge, a celebrity, is having the baby - but it is a girl. He let the news slip in a Today Show interview this morning.
You can see a video clip of the interview HERE.
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