Whittaker gave birth to the couple's daughter in Los Angeles on October 4, according to Us Weekly.
Nunez and Whittaker have apparently named their newborn daughter August Luce Nunez.
Nunez is best known for starring on The Office as accountant Oscar Martinez, a role he has played for nine seasons.
He will appear in the upcoming television movie Prosecuting Casey Anthony as Anthony's attorney Jose Baez.
The Office continues tonight (October 11) at 9/8c on NBC.
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