Britney Spears' fiery public feud with sister Jamie Lynn Spears continues.

Spears 40, took to Instagram Wednesday to repost a statement she deleted quickly after posting Tuesday.

Spears again talked about her time at home after her breakup with Justin Timberlake, but the pop star further slammed Jamie Lynn for being a "selfish little brat."

Britney Spears continued to criticize her sister on social media after the release of Jamie Lynn's memoir.

Britney Spears continued to criticize her sister on social media after the release of Jamie Lynn's memoir. (Image Group LA/Disney Channel via Getty Images)

In Tuesday's deleted post, Spears said both Jamie Lynn and their mother, Lynne Spears, needed to be "slapped" across their faces. Britney explained why in Wednesday's continued post.

"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 ??? And why watching your at length interview … Really 2 HOURS or more ????? And the topic about the knife which is ironically the only lie you've ever told in your whole life … Why is that conversation 20 min ??? and the most degrading to me … OH BUT you don't want to keep talking about it because you don't want to HURT ANYBODY'S feelings …" Spears wrote.

BRITNEY SPEARS SENDS SISTER JAMIE LYNN CEASE AND DESIST, REPORTEDLY REQUESTS MILLIONS FROM FATHER JAMIE

"yet you let it linger forever saying you felt unsafe with and WEIRD …. f--k you Jamie Lynn !!!! My mouth was on the floor the way you talked back to Mamma when I came home … Shocked out of my lined !!!!!! You were f--king 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--t out of your little a--," Spears continued.

Spears and her sister have been publicly feuding in the lead-up to the release of Jamie Lynn's memoir, "Things I Should Have Said." The book was released Jan. 18.

The pop star's lawyer sent Jamie Lynn a cease-and-desist letter Monday.

The pop star's lawyer sent Jamie Lynn a cease-and-desist letter Monday. ( Kevin Winter/Getty Images)

While Britney and Jamie Lynn have been fighting on social media, the "Toxic" singer has taken action privately.

Fox News Digital obtained a cease-and-desist letter that Britney's lawyer, Matthew Rosengart, sent Jamie Lynn Monday, instructing her to "cease and desist from referencing Britney derogatorily during your promotional campaign. If you fail to do so or defame her, Britney will be forced to consider and take all appropriate legal action.

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"We write with hesitation because the last thing Britney wants is to bring more attention to your ill-timed book and its misleading or outrageous claims about her," the letter adds.

Jamie Lynn has sat for various interviews, including "Good Morning America," "Nightline" and the "Call Her Daddy" podcast. In each interview, she described her childhood and how she felt like an "afterthought" growing up.

Britney Spears

Britney Spears has been critical of her family since being freed from her 13-year conservatorship. (Steve Jennings/WireImage)

Spears' latest Instagram post seemingly referenced Jamie Lynn's claims that the pop star locked the two in a room with a knife once, and that Jamie Lynn was allegedly beaten by their mother with a purse.

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Spears has been calling out her family for a lack of support during her 13-year-long conservatorship.

Representatives for Britney, Jamie Lynn and Lynne did not immediately respond to Fox News Digital's request for comment.

Fox News' Nate Day contributed to this report.