Sharon Osbourne's brother has compared her to Hitler and Dracula.
Sharon recently claimed that her estranged sibling David Arden and his friends used to taunt her about her weight when she was younger but David insists she is lying and said he wants nothing to do with her.
Speaking to the Daily Mirror newspaper, David said: "The fat-shaming by me and my friends is complete fiction.
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"With regards to me constantly trying to contact her, utter fantasy, it would be like me wanting to contact Hitler or Dracula.
"Mrs Osbourne has left two messages on my phone in the last 10 years which I have retained for possible future use as valuable material for anyone carrying out research into psychopathy.
"Her usual modus operandi, gross distortion of the truth. It is not in my nature to shame anyone's appearance, however as Mrs Osbourne has shown it is one of her favourite pastimes.
"I think it is time that anything emanating from her mouth should be flagged, Twitter-style."
Last month, Sharon - who has not spoken to David since they fell out 13 years ago over where to lay their father Don Arden to rest - claimed David and his friends used to taunt her about her weight when she was younger.
Speaking on US chat show 'The Talk', Sharon , 67 - who is married to rocker Ozzy Osbourne - said: "I used to get fat shamed by my brother. [He] used to get his friends to join in. It sticks with you.
"At times I was bigger than others. My weight has always [gone up and down], and that's it.
"It's been going on for hundreds of years, people going on about people's weight. And it never will end."