The 30 year old actresses turned fashion designers have always experimented with their clothes and Mary-Kate has revealed they used to design their own outfits growing up.
Ashley Olsen and Mary-Kate Olsen attend WSJ. Magazine's "Innovator Of The Year" Awards at MOMA on October 18, 2012 in New York City. PICTURE: Cindy Ord / AFP
She shared: "When we were younger, being in the public eye was almost part of our role and responsibility - to set the trends at that time or be ahead of fashion. "We would take adult clothing and cut it down to our size, change the proportions. I think from a young age we understood fit in a very different way because we're so petite."
And Mary-Kate enjoys "switching things up" from time to time as that is the "beauty of clothes". She added: "We just want to help women feel however they want to feel. Every once in a while, we want to change our perfume or our haircut; we want to wear heels or flats. We just like to switch it up. That's the beauty of clothes."
Mary-Kate Olsen and Ashley Olsen attend the "Charles James: Beyond Fashion" Costume Institute Gala at the Metropolitan Museum of Art on May 5, 2014 in New York City. PICTURE: Larry Busacca / AFP
The pair have their own womenswear range called Elizabeth and James amongst other clothing lines too and call it the "new luxury". Mary-Kate told Net-a-Porter's The Edit magazine: "We like to say that Elizabeth and James is the new luxury. It's the idea that you can still have fashion, great fabrics and great fits at a lower price point .
"We talk about the mother and the daughter, the comfortable and sexy, masculine and feminine. It's a balance of both." Meanwhile, the designing duo previously admitted the whole process has become "more mathematical" in recent years. Mary-Kate said: "It's important to control the image of your brand, something we have known since we were very young. It's a lot more work but we're up for it.
Ashley Olsen and Mary-Kate Olsen attend the "Manus x Machina: Fashion In An Age Of Technology" Costume Institute Gala at Metropolitan Museum of Art on May 2, 2016 in New York City. PICTURE: Dimitrios Kambouris / AFP
"Design has become really mathematical in a way, and for us, there's a freedom that comes from knowing exactly where we want to go from the start."