Nicole Richie has checked herself into a Los Angeles hospital.
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A rep for the star tells Usmagazine.com, "Nicole has checked into Cedars Sinai where she is being treated for pneumonia. She is doing well."
Citing illness, Richie, 28, bowed out of the Nov. 10 launch of her House of Harlow jewelry at Bebe in L.A.
She also took to her Twitter account a few days back and mentioned she was feeling ill: "ok cold, it's been 6 days. Lets part ways graciously & keep it moving."
In September, she gave birth to son Sparrow, her second child with Joel Madden; daughter Harlow is 22 months old.
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