Celebrity Gossip's

Troubled star Britney Spears is continuing her extreme ramblings - this time accusing her mother, Lynne of sleeping with her ex-hubby Kevin Federline.

The 25-year singer said that her mum was doing so to get close to her grandchildren.

Sources revealed that the 'Toxic' hitmaker flew into a rage after another bust-up and ranted: "I suppose you're sleeping with Kevin now as well?"

Spears and her mum used to be close but they've been at loggerheads since the summer when Britney accused Lynne of being too controlling and ruining her childhood.

Spears has also refused to let her mom see her grandkids Sean Preston and Jayden James.

"Britney is fuming that K-Fed has become so close to her mum," News of the World quoted a source, as saying.