Johnny Depp was surprised when he was asked to be godfather to director pal Tim Burton's son - because the quirky moviemaker couldn't bring himself to do it himself. Instead, Burton asked his wife Helena Bonham Carter to put the idea to the actor. Depp was working alongside Burton on the set of Charlie And The Chocolate Factory when he received a message to call Bonham Carter urgently. And the actor, who quickly agreed to be four-year-old Billy's godfather, was puzzled that Burton hadn't asked him personally. He explains, "This is Tim Burton in a nutshell - we were doing Charlie And The Chocolate Factory and I was on the set... One of my pals comes up and says, 'Helena just called. When you get a moment, she'd like you to give her a call back.' "So I go back to the trailer, call Helena, and say, 'Hey, what's going on?... Is everything all right?' And she says, 'Everything's fine. But, well, you know how Tim is. He wants to know if you'd be... he'd like for you to be Billy's godfather.' "I say, 'But I was just with Tim. I was with him three minutes ago. I had to leave him to walk back to the trailer to call you.' "So she called me to ask because Tim just couldn't. That was his way of asking. I went back to the set and said, `Thank you.' I told him that I was honoured. "It doesn't get heavier than saying, `I'd like you to be the godfather of my son.' But he's not ever going to put himself into a corny kind of situation with a pal. He's like, `Good, yeah, yeah.' Boom. `Let's get back into the work.'" Bonham Carter gave birth to her second child with Burton on Saturday (15Dec07), a girl whose name is currently unknown.