We needed to make a sound that's not gonna fit in with everything else - we wanted to make something that was completely unique and individual to us. We spent a lot of time trying to make a sound that was a One Direction sound. At first it was quite hard to do that, but I'm really happy with the sound.

I thought I had a type but I don't really have a type anymore. I just look for a girl who doesn't take herself too seriously.

My trademark saying is probably “VAS HAPPENIN?!”

I can't swim but if my girlfriend was drowning, I'd still dive in to save her.

We didn't really expect to achieve anything outside of the UK, and it just went crazy. It's just crazy that people know our music. We're just humbled by it.

I was a bit of a handful when I was a kid because I was quite hyperactive. Even in the house my mum used to put me in my pram because I was so full-on.

It's pretty strange because you have images of people in your head when you left, then you just think they're going to be the same when you come back, like time freezes. I have sisters and from the ages of 11 to 13 - it's a big change for girls.