Stamos, 54, took to Instagram to share the happy news.
"From now on, the best part of me will always be my wife and my son," he captioned the sweet snap of his son, Billy, laying on his chest and holding his ring finger. "Welcome Billy Stamos (named after my father) #NotJustanUncleAnymore #Overjoyed."
The Full House star previously opened up to ET about his feelings on becoming a father. "I've waited my whole life for this," he said at the time. "I'm already so emotional and so excited."
"I kissed the boy and said...yes! That's what you do when the sweetest, most romantic Prince Charming treats you like a princess and asks you to be his," the model wrote on Instagram after saying "I do."
What do you think of love birds John Stamos and Caitlin McHugh welcoming a baby boy? Sound off below.
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