PAUL GIAMATTI and VINCE VAUGHN in 'Fred Claus'

Vaughn, who plays Santa's grumpy brother in new movie Fred Claus, admits he stopped believing in St. Nicholas when he was six, but struck a deal with his sisters to keep the myth alive.

He says, "I went to my sisters and said, `Don't tell mum and dad because then we may not get gifts anymore. You got to keep pretending you think there's a Santa Claus.'

"So I was 16 saying, `When is Santa comin' down the chimney?' and finally my dad was like, `Look, son, it's getting weird. You're getting older and you know there's not a Santa Claus but we're gonna keep giving you gifts.'"

But Vaughn could never spoil the magic of Christmas for other kids - like his neighbours did for him when he was six.

He adds, "We just did this promotional thing for Fred Claus and when it was over this 10-year-old kid came running up to me and he says, `Hey Fred, tell your brother to get me something this year!' I looked at him and said, `I got you.'

"So I'm hoping his parents get him something good or otherwise he'll hold me accountable for it."

Source: WENN