Jamie Lynn Spears has called out her sister Britney Spears for making "vague and accusatory posts" on social media instead of telling the truth.

The Sweet Magnolias star discussed her relationship with her older sibling on Good Morning America on Wednesday and the Toxic singer responded on Twitter on Thursday by accusing the actress of trying "to sell a book at my expense".

Jamie Lynn hit back in a lengthy Instagram post several hours later in which she claimed their private conversations are very different to what Britney tells her fans in "vague and accusatory posts" on social media.

"Quite frankly, the things being said are absolutely not the truth, and I have to clarify that, because now it's getting harder for me to rationalize to my oldest daughter why our family continues to get death threats, as a result of their aunt's vague and accusatory posts, especially when we know she could tell the truth, and put an end to all of it in one second if she wanted to," she wrote.

"Sadly, after a lifetime of staying silent, I have come to realize this isn't going to be a reality, and I may have to set the record straight myself in order to protect mine and my family's well being."

The 30-year-old continued by insisting her memoir, Things I Should Have Said, isn't focused on Britney, and she has a career of her own and isn't just "someone's little sister".

"That being said, I hate to burst my sister's bubble, but my book is not about her. I can't help I was born a Spears too, and that some of my experiences involve my sister," she stated.

"There are no sides, and I don't want drama, but I'm speaking my truth to heal my traumas, so I can close this chapter and move forward, and I wish my sister could do the same. No matter what comes, I will always love my big sister, and be here for her. It's time to put an end to the unhealthy chaos that has controlled my life for so long."

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