According to a source close to the family, "Everyone is happy and healthy."
The couple, who married in an ultra-secret ceremony at their Los Angeles home in December of last year, have kept quiet about their relationship from the beginning .
Aside from being spotted together sporadically since 2013, the pair – who Gordon-Levitt says met through "mutual friends" – has managed to keep things under wraps otherwise.
"The girl that I'm with, she really doesn't want to be a part of public celebrity," he said of McCauley in a 2013 interview.
"I get up in movies and I play other people, so when the audience is watching me in movies, I don't want them thinking about me and who I'm dating, and blah blah blah," he added.
Now, with the arrival of their new bundle of joy, there's no doubt that Gordon-Levitt and McCauley have remained happy together.
Congratulations to the couple on the birth of their son!