Kylie Jenner Did Not Get the “Wear Black” Memo While Out With Her Family: See the Style Photos!

Keeping up with Cosmo! Kim Kardashian, Khloe Kardashian, Kourtney Kardashian, Kylie Jenner, and Kris Jenner all stepped out to celebrate Cosmopolitan's 50th birthday — and the ladies' November 2015 cover for the mag, which hails them as "America's First Family" — at Ysabel in West Hollywood on Monday, Oct. 12.

Kim, 34, who's expecting a son with husband Kanye West, hit the pink carpet modeling her go-to pregnancy uniform: a fitted Wolford tube dress, teamed with a long jacket (draped over her shoulders, natch), a choker, and ankle-strap sandals. She slicked back her hair into a low bun, and added a glossy nude lip.

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Kim Kardashian and Kourtney Kardashian

But she wasn't the only one in black at the event! Khloe, 31, (in an American Apparel bodysuit and slitted skirt), Kourtney, 36, (in a wide-leg Balmain jumpsuit), and Kris (in a long-sleeved one-piece and Chanel statement earrings) also donned the hue.

Khloe Kardashian

In fact, the only member of the family who didn't wear black was blonde, bewigged Kylie, 18, who opted for a slouchy white sweater with a matching miniskirt, a blush bag, and gray sandals. Joking about the sartorial snafu via Instagram, she wrote, "I didn't get the 'wear all black' email," captioning a group shot with her family.

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Inside the event, Kris, 59, saluted Cosmo's milestone. "It's been such an honor to be on the cover of the 50th anniversary of Cosmopolitan magazine that…I grew up with, and that my girls have been reading since—oh, my goodness!" the momager joked. "So a toast to [Cosmo] for a job well done. And to my girls, thank you so much for being who you guys are. I love you to death!"

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While the reality stars were the guests of honor at the event, they weren't the only big names present. Sarah Hyland, Julianne Hough, Ashley Tisdale, and Olivia Culpo, to name a few, also came out to celebrate the long-running women's mag.

Which Kardashian-Jenner lady gets your vote for best-dressed at Cosmo's bash? Tweet with @UsWeekly using the hashtag #stylebyUs!

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