Now 17-year-old Kylie's sister Kim, 34, has defended her decision to have the temporary procedure.
Speaking to Access Hollywood at the launch of her new book Selfish, Kim said: "At 10 and 11 years old she'd say, 'Kimmy, how come my lips aren't as big as your buys'?"
Acknowledging Kylie's lips were an insecurity, Kim added: "If it's going to make her feel better then I'm all for it."
![Kylie admitted she's always felt insecure about her lips](https://images.bauerhosting.com/legacy/lifestyle-legacy/08/74761/9cece/b40ee/7f111/8aa0d/5c2d2/kylie-jenner-kim_646x363.jpg?auto=format&w=1440&q=80)
Kim also hit back at critics who have slammed Kylie for lying about having the procedure.
"She didn't lie, it took her a while to actually make that decision and once she decided to plump them, she was still over-lining, then sometimes it would look too big, then she figured out to stop over-lining.
![](https://images.bauerhosting.com/legacy/lifestyle-legacy/f1/06e1a/dfde1/d283f/d6e0c/33007/caa65/wenn22460813_363x646.jpg?auto=format&w=1440&q=80)
"She plumped them and she was happy with it. People think, 'Oh my God she lied for so long – now she's finally come clean' but that's not the case, it took her a while to do it."
In a a teaser for an upcoming episode of Keeping Up With The Kardashians, Khloe, 30, can be seen urging Kylie to come clean about the fillers.