Gossip Girl star Kelly Rutherford became a mom for the second time on Monday -- but her ex is hardly celebrating.

The actress, 40, welcomed a daughter, Helena, in Los Angeles on Monday, an attorney for Rutherford's ex, German businessman Daniel Giersch, tells Usmagazine.com. "We confirm the party's [Daniel Giersch] daughter, Helena, was born yesterday," lawyer Fahi Takesh Hallin told Us on Tuesday.

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But a source tells Us the birth came as a surprise to Giersch, who is currently in the midst of a heated divorce with Rutherford. Giersch had filed paperwork to be notified when Rutherford goes into labor, says the source. But the insider tells Us, "She failed to tell him, and instead he found out this morning on the Internet."

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Adds the source, "He was robbed of an opportunity to be at the hospital when his child was born. He is sad and disappointed."

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After two years of marriage, Rutherford filed for divorce from Giersch in January -- while pregnant with their second child. The two have since engaged in a nasty war of words over who is the better parent as they continue to fight for custody of their son, Hermes, 2. Asked at a May 22 hearing if she and Giersch could have an amicable relationship, Rutherford told reporters: "I don't see it."

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