Bella Hadid, Vittoria Ceretti and Gigi Hadid are seen backstage ahead of the Alberta Ferretti show during Milan Fashion Week Spring/Summer 2018 on September 20, 2017 in Milan, Italy. (Photo by WWD/Rex Features/Shutterstock)

A model presents a creation by designer Katy Nguyen during Vietnam International Fashion Week in Hanoi, Vietnam, Wednesday, November 1, 2017. (Photo by Hau Dinh/AP Photo)

A model presents a creation from the Fyodor Golan catwalk show at London Fashion Week Autumn/Winter 16 in London, Britain February 19, 2016. (Photo by Neil Hall/Reuters)

A model displays shoes during the Ryan LO Autumn/Winter show at London Fashion Week, Friday, February 19, 2016. (Photo by Kirsty Wigglesworth/AP Photo)

A model has her hair done backstage before a fashion show by Greek designer Mary Katrantzou during the Mercedes-Benz China Fashion Week in Beijing, China, 27 March 2016. The fashion week runs until 31 March. (Photo by How Hwee Young/EPA)

Model presents a creation from the Agua de Coco por Liana Thomaz collection during the Sao Paulo Fashion Week in Sao Paulo, Brazil on April 21, 2018. (Photo by Nacho Doce/Reuters)

A model prepares backstage ahead of the Amber & Thomas show during Rosemount Australian Fashion Week Spring/Summer 2011/12 at Overseas Passenger Terminal on May 3, 2011 in Sydney, Australia. (Photo by Ryan Pierse/Getty Images)

Final preperations are made backstage during Graduate Fashion Week at Earls Court on June 6, 2011 in London, England. The event which began in 1991 showcases emerging talent from BA Graduate fashion design courses across the UK and includes exhibition stands and catwalk shows from around 50 universities. (Photo by Dan Kitwood/Getty Images)