The "Parks and Recreation" star and her husband, former "Arrested Development" actor Will Arnett, are already the parents of a toddler named Archie.
Little brother Abel James Arnett weighed 7 pounds, 13 ounces when he was born early Friday, People.com said.
"Amy, Will, Abel and Archie are all healthy and resting comfortably," Poehler's representative told the Web site.
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