The photo was an old shot of Brad Pitt, with Spears, 41, explaining she was sharing the picture "because he looks so much like my uncle, it’s kind of creepy !!!"
"We all have our family issues but I do have a beautiful family !!! My mom and dad were a stunning couple when they were young … like shocking [sic] attractive !!!" the Crossroads star declared, then mentioning her dad's two brothers, who lived with their brood while she was growing up.
The blonde beauty recalled a random memory she had during her childhood.
"When I was 2, the [uncle] that is identical to this picture helped potty train me … my miniature baby toilet was bright yellow but one day when I sat down, there was a crack in the seat and it cut my little booty !!!" the mother-of-two said. "All I remember was he picked me up, we looked in the mirror together and he said 'don’t cry' !!"
However, the pop star's fans didn't see the humor in the odd tidbit, and they were also surprised she didn't prevent people from leaving comments on the upload.
"Sorry Brit… but weird post," one person wrote, with another noting, "Hope you’re safe and happy. ❤️ We all know you’re still being controlled. And you don’t run your insta account."
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Others felt she was trying to let people know that she could have been abused as a kid, while some just thought the post proved she's still in need of a conservatorship, which her father ended in 2021 after 13 years.
"Britney fans need to stop encouraging her madness. This is a grown woman that has no control over her emotions/behavior, and needs attention," they stated. "She blames everyone but herself. Her father was ABSOLUTELY RIGHT."