Kaitlin Olson and Rob McElhenney Welcome Son Leo Grey

The It's Always Sunny in Philadelphia costars welcomed Leo Grey McElhenney at 1:15 a.m. on Thursday, April 5 at their home in Los Angeles, they tell PEOPLE exclusively.

Source: http://feeds.celebritybabies.com/~r/celebrity-babies/~3/mwcA9n4vp7k/

Zhang Ziyi Zoe Saldana Zooey Deschanel Aaliyah Abbie Cornish