Sienna Miller gave birth to her first child, a daughter, in London during the weekend, a source close to the "Factory Girl" actress told People.com.
No other details regarding the baby's birth were immediately available.
Miller, 30, has been dating actor Tom Sturridge, 26, for more than a year, but the couple has kept their relationship out of the press.
Her previous romances with actor Jude Law, who cheated on her with his children's nanny, and Balthazar Getty, who was married with children when he dated Miller, made her a target for the tabloid media.
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