Often, the girl in the 'Girl in the Attic' true story was a victim of a difficult family situation. She could be a child who was born into a dysfunctional family, perhaps where one of the parents or guardians had some sort of psychological issue that led them to confine her to the attic.
We don't have enough information from just the title to identify the girl. She could be a young girl from a small town who got into a strange situation in the closet. Or she could be a girl from a big city facing some sort of domestic issue that led her to be in the closet. There are countless possibilities until we actually read the story.
I'm not sure specifically which 'girl in the box' true story you are referring to as there could be multiple cases. But generally, it was a girl who became a victim of some sort of cruel situation that led to her being in a box.
Sadly, I don't recall the specific name of the girl in the 'Girl in the Basement' true story. However, she was a young woman who had her life turned upside down when she was confined in that basement. She was at the mercy of her captor and had to endure so much.
I'm not sure specifically who the girl is without more details about the story. It could be an ordinary girl who unfortunately ended up in this situation.