'Disgusted' Britney Spears accuses sister Jamie Lynn of selling a book 'at my expense'

After Jamie Lynn Spears (right) said that Britney Spears (left) was 'erratic, paranoid' and 'spiraling' in an interview, the 'Toxic' singer took to Instagram on Jan 13 to air her grievances about her sister. Photos: AFP and Handout

After Jamie Lynn said that the Toxic singer was "erratic, paranoid" and "spiraling" during a series of ABC News interviews last week, Britney took to Instagram Thursday (Jan 13) to air her grievances about her sister, explaining that she had a fever of 104 degrees while the latest events transpired.

"It was actually kind of nice having a fever so high cause I had to surrender to not caring," Britney, 40, wrote in a series of Notes app images posted Thursday on Twitter that appeared to accuse her sister of being an opportunist.