Voices come to me but to maintain them is hard work. They go away just as easily, so I have to remember them and that takes work. With Sid, I needed to make sure you could understand what he is saying, his enunciation. Sometimes I couldn't even say my own name [his name] in his voice. It sounds like 'Shid', it sounds a bit like he has a lisp.

I walked around my apartment with food in my mouth asking myself: "How do I come up with this voice?" Then I found the voice. I called the director and said on the phone: "Guess who you're talking to Chris? Sid, that's right Sid!" And that's how I came up with the voice. That's a true story.

It's all about respect; he's looking for respect from his buddies. In the last one he just wanted to hang out, to be part of the group, but this time he wants more from his friends. And without giving the story away, he finally gets something that he has been looking for when the mini sloths kidnap him and take him to their tribal area. He gets to be the Fire King and they worship him and there is an amazing scene with a "call and response" sequence in the style of Cab Callow [the legendary American jazz singer and band leader] between him and his audience.

I would be jokesmithing. I had files with tons of disses that I would try to write as I was on the train going to school.

Don't confuse the beginning of my world with the breakup of yours.

You have the hilarity and the great production. These films are distinctive because they are not just topical, they tell good stories and they let scenes play out physically. Apart from the dialogue, the characters also have a non-verbal existence, for example with Scrat.

After kids leave the house, they can decide to do whatever they want, but while they're under my roof, they're going to be lawyers or writers or something, something important, anything except actors.