Grab your cans of wine and milksteak--it's time for an "It's Always Sunny in Philadelphia' celebration!

'It's Always Sunny' co-stars Kaitlin Olson and Rob McElhenney welcomed a baby boy on Wednesday, PEOPLE exclusively reports. Their son, Axel Lee McElhenney, was born at 12:52 p.m. on Sept. 1 at their home in California.

"I went into labor at the Phillies/Dodgers game on Tuesday night. As soon as Ryan Howard hit a three-run home run, we felt comfortable leaving to go have our baby. We love him like crazy, even though he made us miss the second half of the game," Olsen told the magazine.