John Stamos has become a father for the first time.

The 'Fuller House' actor and his wife Caitin McHugh have welcomed a son into the world and have named the youngster in honour of the 54-year-old star's beloved late father, Billy.

John - who is best known for playing Uncle Jesse in 'Full House' and 'Fuller House' - revealed the happy news on Instagram by sharing a black and white photo of the baby resting on his chest and clutching his finger.

He captioned the image: ''From now on, the best part of me will always be my wife and my son. Welcome Billy Stamos (named after my father) #NotJustanUncleAnymore #Overjoyed (sic)''

John, who was previously married to Rebecca Romijn, admitted last year he'd always wanted to be a father and felt it would be a ''tragedy'' if he never had kids.

He previously said: ''It's just taken me a lot longer than I anticipated.

''It would be a tragedy if I didn't have children and I finally found the right woman -- the perfect woman. I know my parents are smiling down. I know they would love her. She's a gentle, kind, graceful soul who would be a good mother.''

And the former 'E.R'. actor previously praised Caitlin - who he married in February - for dealing with her pregnancy ''like a champ''.

He said: ''She's so beautiful pregnant. She's so magical.

''She is the most graceful person I've ever met in my life, and she's handling pregnancy like a champ. Every day I say, 'You're doing so great, you're doing so great.'

''Just every day I'm with her I just realise, first of all, how lucky I am, but what a special human she is. She's magical. She floats into a room. I've never heard her say a bad word about anybody.''

John also insisted he doesn't have any nerves about becoming a dad.

He said: ''I'm not nervous at all. I've been not nervous about getting married - I just knew it was the right thing. I'm not nervous about having a kid, I'm not nervous about having a kid with her.''