Simpson's mum furious with her Parton performance

Jessica Simpson's mother reportedly lashed out at her daughter in front of Dolly Parton and US President George W Bush after the pop star forgot the words to the country star's 9 To 5 at Sunday's the recent Kennedy Center Honours.

Reports suggest Tina Simpson was furious with her daughter and told her she should quit the music business if she didn't want to put in the work.

According to website TMZ.com, Tina said her performance was "embarrassing" and "unprofessional".

Simpson's mother was further incensed because Jessica had failed to turn up at a dress rehearsal and hadn't bothered to learn the words to the song, instead relying on cue cards during the performance.

The show's producers insisted that she re-tape the performance without anyone in the audience if she wanted to be included in the show's subsequent broadcast on December 26.

Adds a source for US network CBS adds: "We almost cut her out of the show."