The 44-year-old pop star shared a throwback photograph of her sons Sean Preston, now 20, and Jayden James, now 19, running on the beach when they were younger, and hit out at her parents, Jamie and Lynne Spears, for "secretly" taking them to a beach without her during her conservatorship.
Spears wrote on X: "Those two little bodies came out of my belly. Yes, they are mine ... Unfortunately it wasn't until 5 years ago that I saw they were secretly taken to the beach by my mom and dad ... The whole summer.
"I wondered why I wasn't a part of their cool secret outings. I felt demoralized to live in a country where it was accepted for people like my mom and dad to live secret lives with my children. I honestly went to my knees and cried for two months."
While Spears claims her parents enjoyed secret outings with her children - whose father is her ex-husband Kevin Federline - she alleged that she was banned from certain social situations by her father.
She claims he forbid her from going "to a diner ever again to eat a hamburger with a new extremely cool friend I had found cuz all the attention I got from the paps after being held in my home for four months offended him".
She went on: "I was never allowed to see my friend again or go out to old fashioned hamburger diners. If you know me I love food."
Spears - who spent 13 years in a conservatorship that controlled her finances, career and personal life - also alleged she was "brainwashed" and taken "advantage" of.
She said: "Society doesn't understand the real effects to this very day of the rights and freedoms anyone should be able to have. I never got to be me, the real Spears ... I used to be unbelievably intelligent and 100 per cent I was brainwashed into an ignorant system where every person took advantage of me ... I firmly believe I am an angel, and it hurts. Time is in a different realm when you're an angel ... I miss the excitement in my eyes, being alive when I was younger, always so eager to please and hungry for life."