Kelly welcomed Helena Grace Rutherford Giersch in Los Angeles at 9:20 PM.
U.S. & World
Her newest little one, sister to her son, Hermes, 2, weighed in at 8 lbs., 12 oz.
"Kelly and the baby are doing just fine," Kelly's rep said in a statement to Access.
Kelly is currently embroiled in divorce proceedings with Daniel Giersch, the father of both of her children.
She filed for divorce on December 30, 2008.
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