Kelly Osbourne is losing patience with a prankster who has made a string of abusive late night calls to her cell phone.

Osbourne, daughter of legendary rocker Ozzy, has taken to the Internet to announce she has been receiving strange calls for the last two weeks.

Osbourne writes on social networking site Twitter.com, "It's a U.K. number they keep calling me fat and saying they are going to stab me! How pathetic!"

The former TV wildchild suspects the number was stolen from a friend of her model boyfriend Luke Worrall, and posts the number on Twitter with a threat of her own.

She writes, "They have been calling me for about two weeks and they know way to much but they should have thought twice about f**king me with me."