Mrs O was quoted as saying that the teen pop sensation would not "stand the test of time" and claiming he looks like a "little boy".
And according to Digital Spy, Biebs has hit back at the former The X Factor judge on Twitter.
JB wrote: "doubt me...i like it," before adding: "im working on something special."
Then, leaving Beliebers in no doubt that he was referring to Osbourne's predictions, Justin posted a link to his latest video Beauty And A Beat, tweeting the words: "Not worried sharon."
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