"Yesterday @caceecobb and I welcomed the most amazing little boy into our lives! Oh Happy Day!!" Faison tweeted Friday August 16.
"The happiest day of my life," Cobb also tweeted.
Faison spoke with US Weekly in February following the news the couple had been expecting.
Indeed, Faison couldn't be happier about his fifth little bundle of joy. "I'm just excited for CaCee, she's probably the most loving person I've ever met in my life.
"And so for her to have a baby that she can love and you know, raise, and that we can raise together, and she can influence and teach and stuff like that, it just, I know that it'll be a really good human being when it's older."
Cacee Cobb was introduced to the public on Jessica Simpsons reality show “Newlyweds: Nick and Jessica with her former husband Nick Lachey. Cobb is Simpson’s best friend and former personal assistant.
This new addition is 35-year-old Cobbs first and 38-year-old Faison’s fifth child. The couple has been married since December 2012.