For once, it isn't Kylie Jenner's lips causing a stir on the internet, but her older sister Kendall's.
The sisters did a Facebook Live on Tuesday, and in pics Kendall and Kylie both shared on social media, fans couldn't help but notice 21-year-old Kendall's bigger-than-usual lips.
WATCH: Kylie Jenner Shares 3-Step Lip Kit Tutorial On How to Achieve Her Perfect Pout
Given 19-year-old Kylie's admitted use of lip fillers, some fans were quick to comment on Kendall's pucker.
But Kylie later explained she's actually the one behind Kendall's new look, apologizing for being a little overzealous with her use of lip liner on her supermodel sis.
"You guys, Kendall let me overline her lip today with lipliner and everyone thinks she got lip injections," Kylie confessed in a Snapchat, while Kendall laughed in the background with a dog filter over her face. "I'm sorry, Kendall."
Interestingly enough, in a Keeping Up With the Kardashians episode last May, Kylie revealed Kendall wasn't a big fan of her enhanced lips. "Kendall said they look too big yesterday," she tells their big sister Kim Kardashian.
"No one needs anything," Kendall later comments. "Everyone is beautiful. ... You guys don't need to worry about this so much."
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Meanwhile, Kendall recently ended her Instagram detox after one week. Earlier in the week, she explained her decision to temporarily leave the popular photo-sharing app.
"I don't know, I just wanted to detox," Kendall told Ellen DeGeneres. "I just felt like I wanted a little bit of a break. I'm always on it. I would wake up in the morning and look at it first thing, I'd go to bed and it's the last thing I would look at. I felt a little too dependent on it, so I wanted to take a minute to detox."
"It's kind of a nice, refreshing feeling," she added. "I'm away from my phone so much more. You start to engage in, like, real life, and you have to deal with real people right in front of you, so it's kind of really nice to be away from it, even if it's just Instagram."