Billy Crystal has an extra special connection to his new baby grandson because he was born on the actor's 65th birthday.

The Princess Bride star's producer daughter Lindsay went into labour during her father's celebratory dinner on 14 March (13) and though Crystal was initially ambivalent about sharing his big day with another relative, he insists the tot's birth was the greatest gift.

During an appearance on The Tonight Show with Jay Leno on Monday (17Jun13), he said, "We're at my daughter Lindsay's house and when I get there, she says, 'I think I'm in labour. I think so. I'm not sure...' So now I'm thinking, 'If it comes tonight, is it good for the baby to have the same birthday as me?' But then I'm thinking, 'Is it good for me to have the same birthday as him or her?'

"This was a milestone, my 65th. Is my 70th (birthday party) gonna be at Chuck E. Cheese (children's play centre). What am I gonna do?

"So we're eating dinner, and from the other room, you hear, 'Wow. Wow...' She's in labour... He was born that night. It's very exciting."