The actress, 40, is expecting baby No. 4 with longtime partner Paul Thomas Anderson, 42, according to The Hollywood Reporter.
The "Saturday Night Live" alum and her director beau are already parents to Pearl, 7, Lucille, 3, and Jack, 19 months.
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The pregnancy news is the latest twist in the ongoing "Up All Night" saga at NBC.
After replacing their showrunner and changing the plot of the Lorne Michaels-produced show ...
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