Britney Spears has reportedly sent a cease and desist letter to sister Jamie Lynn Spears after she called the pop star’s behaviour “erratic”, “paranoid” and “spiralling” in her press tour.

Jamie Lynn’s memoir, called ‘Things I Should Have Said’, was released this week with the book discussing pivotal moments of Britney’s life.

In a new letter, obtained by Page Six, Britney’s lawyer Mathew Rosengart said Jamie Lynn’s book contained “misleading or outrageous” claims about the singer, adding that she has “exploited her for monetary gain”.

“You recently reportedly stated that the book was ‘not about her.’ She takes you at your word and we, therefore, demand that you cease and desist from referencing Britney derogatorily during your promotional campaign,” part of the statement read.

“If you fail to do so or defame her, Britney will be forced to consider and take all appropriate legal action.”

The sisters have been in a very public feud since Britney was freed from her conservatorship in November.

The 39-year-old now has power over her life, and has regained control over her own mental, personal and financial decisions for the first time since 2008.

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