https://en.m.wikipedia.org/wiki/Immaculate_Conception#:~:text=Popular%20devotion%20and%20Ineffabilis%20Deus,-The%20eventual%20creation&text=1303%E2%80%931373)%20told%20how%20Mary,and%20free%20of%20sexual%20lust.

"Popular devotion and Ineffabilis Deus

The eventual creation of the dogma was due more to popular devotion than scholarship.[34] The Immaculate Conception became a popular subject in literature and art,[6] and some devotees went so far as to hold that Anne had conceived Mary by kissing her husband Joachim, and that Anne's father and grandmother had likewise been conceived without sexual intercourse, although Bridget of Sweden (c. 1303–1373) told how Mary herself had revealed to her that Anne and Joachim conceived their daughter through a sexual union which was sinless because it was pure and free of sexual lust.[35]"

It's the "original" that people misunderstand repeatedly to the point they think it's a different story.