Kylie's lips, in particular, were a focus of Sunday's KUWTK

Credit: Jon Kopaloff/FilmMagic

Even the Kardashians have their insecurities, and perhaps none more so than 17-year-old Kylie Jenner, who finally revealed on Sunday’s episode of Keeping Up with the Kardashians that she has, indeed, enhanced her lips with temporary fillers.

Khloé‘s own insecurities were used to open the conversation about self-image when Kim and Kendall accompanied her to an intimate cosmetic procedure. As Khloé had cellulite and stretch marks lasered off of her famous Kardashian derrière, Kim and Kendall looked on, hilariously munching on pastries and chatting idly about their sister’s tush. As you do, right? Sister stuff.

As Khloé said, “When you are photographed all the time, it’s natural to have insecurities or to want to change certain things about yourself.”

Enter talk of Kylie’s lips.

RELATED VIDEO: Kylie’s Snapchat Slip-up

Khloé, Kim and Kendall discussed their youngest sister over lunch and, while they were largely supportive of Kylie’s choice to inject her lips with temporary fillers, Kendall said that “[Kylie’s] a beautiful girl. I don’t think she needs anything.”

However, Kylie clearly was not ready to talk about her lips. The teen has been dodging the question for close to a year now, insisting that her pout is the work of carefully applied lip liner. “It’s just an insecurity of mine,” she said of her fillers. “It’s what I wanted to do.” At an event for her line of clip-in hair extensions, Kylie was taken aback when a reporter asked after her lips and so she turned to Khloé and, later, Kim, for advice.

Kim, who admitted during the episode that she feels insecure about her psoriasis as well as her weight, told Kylie that she needed to be proud and own up to what she had done, though she warned her not to get “carried away.” Kendall, for her part, had no idea why anyone was even “freaking out or talking about this. No one needs anything – everybody’s beautiful!” (Kendall was an actual treasure this week. More Kendall on KUWTK, please!)

“If something makes you feel insecure and you’ve been feeling that way forever, who doesn’t want to look amazing? You only have one life to live,” Kim told Kylie, also sharing that she, herself, feels “so insecure” about her weight these days and that she “cannot leave the house without Spanx.”

“We all have eyes on us all the time,” Kylie told KUWTK cameras. “Especially for me, at my age, trying to find myself. It’s hard to not let it affect you. Having older sisters with some of the same insecurities as me helps me a lot and makes me feel like it’s okay.”

Kylie has gone out of her way of late to show that she’s mature for her age, but she showed her years once more when she admitted, “It intimidates me that people are so quick to judge me.”

Keeping Up with the Kardashians airs Sundays (9 p.m. ET) on E!