Charlie Day and Mary Elizabeth Ellis Charlie Day and Mary Elizabeth Ellis

It's Always Sunny in Philadelphia stars Charlie Day and Mary Elizabeth Ellis welcomed a baby boy Thursday, People reports.

Russell Wallace Day weighed in at 7 pounds, 13 ounces.

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"We are overjoyed and overwhelmed at the amount of love that ushered our baby into the world," the couple told the magazine.

Day, 35, and Ellis, 32, wed in March 2006.