The Britney Spears and Jamie Lynn Spears saga continues.

After the release of Jamie Lynn's memoir Things I Should Have Said and a TV and media tour including appearances on the "Call Her Daddy" podcast and Good Morning America, Britney had some things to get off her chest.

In an Instagram post Wednesday afternoon, Britney shared a memory from after her and Justin Timberlake had just broken up. She said she "was a ghost" while witnessing Jamie Lynn get served chocolate milkshakes by their mother, to which Jamie Lynn was "f****** hateful" and "a selfish little brat."

"My Mamma was on paid medication and could barely hold a conversation in the house because her and my dad split and she was more messed up than anything !!!! I remember her sitting on the floor in a conversation and she never got up... and I'm sorry Jamie Lynn, I wasn't strong enough to do what should have been done ... slapped you and Mamma right across your f****** faces !!!!! And WHY do I say that ??? You selfish little brat !!! Saying how weird and dumb it was that I bought a house for Mamma !!!! She was so proud and you told that interview girl that it was just weird .... LIKE I GUESS I WILL JUST WALK IN THESE HALLS ... Why did you say that ???"

Britney continued:

"F*** you Jamie Lynn !!!! My mouth was on the floor the way you talked back to Mamma when I came home ... Shocked out of my mind!!!!!! You were f****** hateful to her and I know Mamma had been lazy with me but I'm sorry you deserved WAY MORE than a purse knocked at you by Mamma ... She should have WHIPPED YOUR A** ...Poor Mamma took it too just like I did in the end ... She worshipped you too much I know but if you came out of my stomach I would have popped the s*** out of your little a** ..."

Britney added Jamie Lynn lied about "feeling bad for me in the breakup," but said Jamie Lynn and all her friends "dyed your hair like Christina Aguilera and you no longer would play with me anymore !!!!"

She concluded her message with:

"I NEVER shut you out ever ... I get it, you were 12 but you were f****** hateful to Mamma being cool with your stupid dark hair ... You can paint it however you like but dear child ..... YOU shut me out when i needed you the most !!!! Writing in your book saying I wasn't like your mom anymore ... No, you hurt me."

Britney recently sent Jamie Lynn a cease and desist for "referencing Britney derogatorily" during the book's promotional campaign.

“Britney has not read and does not intend to read your book, she and millions of her fans were shocked to see how you have exploited her for monetary gain," the letter said. "She will not tolerate it, nor should she."