Specific to the set she bought, the "Casteel Series", it's about a poor Appalachian family, starting with "Heaven" who, at various points, is nearly raped by her father, is physically abused by her father, has all her siblings "sold off" to various people before being sold herself, is coerced into sex with her "adoptive" father, is physically/mentally abused by her "adoptive" mother, is raped by her step-grandfather, mentally abused by her grandmother, has sex with her uncle before moving focus to her daughter "Annie" who gets paralyzed in a wreck that kills her mother (Heaven) and father, then is physically and mentally abused by a hired nurse, then by her great-grandfather (same step-grandfather) who then tries to rape her.
This is all sprinkled with a generous helping of plot twists a' la "the man she thought was her father isn't really" / "this person is dead BUT WAIT no he's not, he changed his name and is living in "hiding" / close sibling/friend/other relation to the protagonist dies a horrible death" sort of thing.
Also, only the half the series and the 2 before it were actually written "by" V.C. Andrews, the rest were written by Andrew Neiderman, who was (somewhat disturbingly) a former schoolteacher and the author of The Devil's Advocate starring Keanu Reeves and a bunch of other ppl I don't remember right now.