I was wondering about the title of a book...?

I was wondering what the name of this book is.Its about a girl.She is kinda a loner and doesn't have too many friends.Her mom is a lawyer and has a case in the city and she goes with her.The girl always has these little day dream things because she was kidnapped when she was younger.It was all because her baby sitter's boyfriend was trying to get back at the mom for sending a family member to jail.I wanted to buy it.Pretty good book.