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)

Models present creations by fashion design students of the Taiwanese Shih Chien university at the Berlin Fashion Week Autumn/Winter 2016 in Berlin, Germany, January 22, 2016. (Photo by Fabrizio Bensch/Reuters)

A model walks the runway for Chromat during New York Fashion Week: The Shows at Industria Studios on February 9, 2018 in New York City. (Photo by Noam Galai/Getty Images for Chromat)

A model prepares backstage of the House of Holland catwalk show during London Fashion Week Women's A/W19 in London, Britain on February 16, 2019. (Photo by Henry Nicholls/Reuters)