I first read this as a teenager, in fact everyone in my class was reading this book and its follow-ups ('Petals On The Wind', 'If There Be Thorns','Seeds of Yesterday' and 'Garden of Shadows'). This was Andrews best novel, neither she or her ghost-writer have ever managed to top this.
The blonde Dollanger family live a happy golden life in 50's suburbia. Then the father dies in a car crash that the police officer makes sure to describe in graphic detail. The useless spendthrift mother begs her long estranged family for help and they agree. So mother and her four blonde happy kids head off to the Foxworth Mansion. There the kids - Chris, Cathy, Cory and Carrie - learn that they are to live in one room and an attic until their mother wins back her father's love. She lost his love when she married his half-brother. Yes the kids parents were half-uncle and half-niece, eeeeewww.
The children spend days in the attic, days that become weeks, that turn into months and which stretch into years. Their grandmother who despises them is cruel to them and their mother stops caring about them as she has her father's billions to enjoy. Eventually after over three years of abuse and betrayal, the kids stop being passive and make a break for freedom.
Yes the prose is purple and the Chris/Cathy dynamic is exceedingly creepy but this is a very good gothic horror. The mother's rejection of her children because of greed is chilling, she is a thoroughly hateable character. It takes time but her children learn to hate her. However Cathy and co still idolise their father despite the knowledge that he eloped with his younger half-niece.
The follow up books ('Petals On The Wind', 'If There Be Thorns', 'Seeds of Yesterday', 'Garden of Shadows') watered down the horror, introduced scores of new characters and brought back presumed dead characters, gave Cathy snotty kids, had numerous fires and bible bashing fruitcakes. This is recommended.