Despite a stint in rehab for "emotional and physical issues" in November 2010, those close to Demi say there are a few habits she didn't drop.
"Demi has really busted her butt to get her career back after the incident with the Jonas Brothers backup dancer and rehab and stuff," an insider exclusively told RadarOnline.com.
"But she's not as sober as she's leading everyone to believe and is still partying hard."
A second source claims Demi, 19, isn't as reckless as she once was with her partying and keeps it away from the prying eyes of the paparazzi and safe within her close-knit circle of friends.
“It’s really irresponsible to be rapping about drugs in front of kids,” Demi spat at the two hopefuls.
After they attempted to make excuses, Demi responded: “You talked about bath salts. I heard you."
"She's really excited about the gig on the The X Factor and is using it as a platform to push her clean image on the public," the source said.
"So she really needs to keep her partying under control."
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