On Saturday, the reality star, 17, took to Twitter to slam the rumors of drug use, insisting she's not the "wild child" people make her out to be.
According to a Kylie pal, her family doesn't think she's "out of control," but "a few are worried" about her boyfriend Tyga's influence on her.
"A lot of Tyga's friends are enablers," the friend says. "That makes her mom the most nervous. She doesn't want Kylie getting off track."
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The 25-year-old rapper has been romantically linked to Kylie since September, and the two have kept their relationship "under wraps as much as possible for obvious reasons," the friend says. "Her parents know she is going to date who she wants, but they are worried he will have a negative impact on her decision-making."
In the last year, Kylie's appearance has changed dramatically, and she is often criticized for looking much older than her age. On Sunday's episode of KUWTK, she finally copped to cosmetically enhancing her lips.
"She's become a perfectionist because she feels like she needs to be just as sexy as her other siblings, specifically Kendall and Khloé," the pal says. "She doesn't feel inadequate next to them, but she's willing to do whatever she can to herself to make her feel like she's looked at by the public in the same way."
Kylie, who plans to move out into her own Calabasas mansion "the second" she turns 18, "is obsessed with the attention and knows that acting a little scandalous here and there will keep her in the spotlight," the friend says.