Jaden Smith insists he and his sister Willow were "much, much cooler" before becoming famous.

Willow and Jaden Smith

Willow and Jaden Smith

The 18-year-old actor and his 15-year-old singer sister - who are the children of Will Smith and Jada Pinkett Smith - are known for their quirky fashion choices but the 'Karate Kid' star claims they used to push boundaries and be more "method" in the sartorial stakes before people began noticing what they wore.

He said: "Nobody knows that Willow and I were much, much cooler before. Like, before people were looking at the things that we were doing, we were so much more, like, method with fashion. We really went all the way. We went the extra mile on everything because there was no one looking at us.

"We've been through the roof, with ludicrous fashion ideas since we were extremely young."

And Willow believes her mother's matter-of-fact opinion on their fashion choices helped them develop confidence in their outrageous ensembles because they learned what people thought didn't matter as much as how they felt.

Speaking to Pharrell Williams for Interview magazine, she said: "Me and Jaden, when we were younger ... Ooh! We would wear the craziest things. Jaden would only wear his Spider-Man costume. I would freaking mismatch every single shirt and pants in my closet. We would just be so rambunctious with our clothing choices.

"And when we were old enough to start dressing ourselves, my mom was like, 'Are you sure you want to go out like that?' And me and Jaden would be like, 'You know what? Yes.' And she'd totally accept it. I feel like that's where most of our confidence comes from. Because we weren't told, 'Oh, you don't look good in that. You look crazy. People are gonna think this about you.'

"Like, obviously, that was going to be happening regardless, but it wasn't like that ruled what we did or the choices that we made."