Looking for a book about a Heroine is thought to be the offspring of a rape

[BB]

I’m looking for a book where a woman conceived a child a few days before she was raped and everybody, including the mother, thought the child was a product of the attack.
She kept the child (a daughter) but the whole family, mother included, was mean to her.
The girls siblings got huge birthday parties and gifts, she didn’t. Everybody in the family, except for her, had a study fund. The only one who cared about her was her godfather. Her siblings got cars on their eighteenth birthday and she was hoping to get one to.
I think, when she went home after school on her birthday, her parents were waiting outside for her with all her stuff packed and told her that they did their duty and that she is not on her own.
They found out years later, when she was in her twenties, when her biological father became ill, that she was his biological daughter.

I’m asking for someone else searching. And these are all the details I have.
Please help!!

[Kris]

BB, what is the story's time period and location - country, region, big city/small town?

How did the family become rich? What were her parents' jobs or inheritances?

Is there romance?

[Shelia]

Following

[MJ]

Me too

[Nicola]

Following I seen it posted a few times and now want to read it :)