John Stamos' son was six weeks premature.
Caitlin McHugh Stamos and John Stamos
The 55-year-old actor and his wife Caitlin McHugh Stamos welcomed baby Billy into the world in April 2018 and they have admitted the early days with their little boy were "very scary" because the tot was so "fragile"
Caitlin said: "He wasn't fully baked, so that was very scary in the beginning.
"He was very, very small ... fragile, little. Every time [he] fell asleep, you're like, 'Please wake up.' [We were] constantly checking to make sure he was still breathing."
But despite the tough early weeks with their son, the couple have some funny memories of his birth.
John joked to People magazine: "It all started when [Caitlin] had contractions, [but then] we went to the doctor and he said, 'It's not ready, why don't you go home and have a glass of wine?'.
"She normally doesn't drink, and hadn't drank for nine months ... she had one glass of wine and she was hammered."
Caitlin added: "It was really funny. I get to the hospital and I said, 'I already had a glass of wine, now it's a party!' Then they gave me the epidural and I was laughing all over the place."
The 'Fuller House' actor - who married the 32-year-old model-and-actress two months before their son was born - thinks he was "always meant" to be a dad.
He said: "I waited a long time for a kid. I just had to meet the right person to do it with, and to straighten my life out. I was always meant to be a father, I think."
And Caitlin thinks her husband took to fatherhood easily.
She said: "He's a natural. He would joke around about how he was never going to change a diaper, but he's pretty good at it!"
The couple are thrilled to have such a "happy", fun-loving son.
Caitlin said: "He's such a happy, giggly guy. Fake sneezes make him laugh. But not real sneezes. Real sneezes kind of freak him out."
John added: "And he's a hambone. I don't know where he gets it from!"
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