The presenter and her DJ partner - real name Norman Cook - welcomed new daughter Nelly May Lois Cook on Thursday. The baby is a sibling to the couple's 8-year-old son Woody.
A statement from the pair reads: "Mum, Dad and big brother Woody are doing great. They are the happiest mama and dad in the world."
The news comes several months after Cook vowed to stay sober following a stint in rehab to fight his alcoholism.
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