Kelly Osbourne is facing a lawsuit from hairstylist Michelle Pugh, the mistress of her father Ozzy Osbourne.

In May, when news of Ozzy's years-long affair with Pugh broke, Kelly unleashed a series of tweets directed at Pugh - even tweeting out Pugh' phone number and claiming Pugh abused the 70-year-old rocker.

"I'm not asking for anyone's approval," Pugh said. "But the difference between someone's disapproval, and shaming and harassing publicly, that's verbal abuse."

Pugh is suing Kelly for defamation, intentional infliction or emotional distress and public disclosure of private facts saying that Kelly's tweets and the ensuing backlash have caused Pugh emotional distress and have caused her to lose business.

Ozzy has since entered into "intense therapy" for sex addiction and wife Sharon is standing by his side.