Kendall and Kylie Jenner, the youngest sisters in the Kardashian-Jenner clan, don't wanna grow up.
The Keeping Up with the Kardashians stars shared with U.K. newspaper The Sunday Times' Style magazine that they have a fear of aging.
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"I'm scared of the day I turn 19," Kylie, 17, said. "I really don't want to grow past 18."
The Times said Kylie then turned to her 19-year-old sister and said, "You'll be 20 this year -- that's crazy. And any second you'll be, like, 21, 22, 23..."
The girls have grown up in the public eye since first appearing on KUWTK in 2007 at the ages of 12 (Kendall) and 10 (Kylie).
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"It's just scary to think how fast everything is rolling and you can't stop it. It's rolling right now," Kendall said of growing up. "You see a picture and you've changed so much in a year."
"I've done so much, physically and whatever," Kylie added.
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Thanks to their family's fame and their social media savviness, the sisters have over 25 million Instagram followers each and it's only growing thanks to bikini pics like these that Kylie posted on Sunday.
Meanwhile, Kendall's cheeky photo she posted on Friday was also trending over the weekend.
Still, the sisters aren't as big of fans of social media as one would think given how often they post.
"I think social media has taken over for our generation," Kendall said. "It's a big part of our lives and it's kind of sad."
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"I hate it sometimes, like, I literally want to throw my phone so I can't look at it," she added. "It's all a made-up world if you think about it. Social media, everything, this interview, everything. It's not real. It's pretty crazy."
Regardless, the teens are using social media to their advantage. TopShop shared an Instagram image on Sunday, revealing the sisters are launching a collection at the store.
Kylie has even used her Instagram to fight back at body shamers. See what she shared when she admitted to gaining a little bit of weight.