Earlier this week, Bella Hadid finally turned 21, a milestone she celebrated with a dinner with her parents, before sneaking off with her sister Gigi to the private party thrown for her by none other than Drake. And while Bella was the birthday girl, and stood out in skin-tight Dolce & Gabbana with a slit that went up the entire dress, it was actually Gigi who stole the show, thanks to her custom ensemble by Pamella Roland, which was entirely baby blue, right down to her periwinkle heels.

As usual, Gigi was simply reprising her role of being the first to brave next season's trends. The blue she'd opted for matched two equally coordinated looks by Sies Marjan on the runway last month at New York Fashion Week, where the buzzy label joined Tom Ford in showing off a couple of head-to-toe neon orange looks for those looking to be even more can't-miss than the Hadids, too.

Tom Ford, Sies Marjan, and Mansur Gavriel during New York Fashion Week spring 2018.

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Of course, dressing monochromatically is nothing new for New Yorkers. What is new, however, is that the style is no longer limited to all-black. The allure of wearing all Valentino red, for example, which the brand updated earlier this month in the form of sheer shirts and sleeveless leather motorcycle jackets, made its most notable crossing over from Milan last fall when Solange stepped out in a blood-red ensemble in New York, around the same time Fendi tried it out on models like Kendall Jenner—and gave nearly every single model a pair of red boots to walk the runway. After Tilda Swinton made like Solange and wore an all-red suit on her Doctor Strange premiere circuit, no wonder Mansur Gavriel included a few all-red looks in their debut ready-to-wear collection last month—with some all-yellow and all-periwinkle looks thrown in there for good measure, too.

More than enough street style stars tried out head-to-toe red in particular this past Fashion Month, too, but about a week after it wrapped, Gigi proved she was much, much more ahead of the trend than we thought. Her throwback birthday Instagram for Bella doubled as evidence that she's actually been dressing monochromatically—and wearing Valentino red, down to her two scrunchies—for a full 21 years now, stretching back to the very day her sister was born.

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