What's the Name of That Book??? discussion

In 4th Grade, which was 2006-7 for me, my teacher had us read this book. Basically it was about this girl who moved into this house and had like a way younger brother, and there was a girl who lived there before her who had died, up in the bluffs. Think it took place in california, but not sure. Anyway, SPOILER, the girls stepdad killed her and her ghost leaves clues to the alive girl about her death. The girl was pushed over a cliff by the man after something happened, I don't remember what, and in the end the living girl gets pursued by the same man but the ghost of the other girl saves her and pushed her murderer of the bluff. Reading over this, it's kind of shocking that a class of 9 year olds was meant to read this, but it's a children's book for sure and the only details I can remember from it was the girl with the little brother, the ghost who died on the bluffs, and how the ghost killed the murderer in the end when he was pursuing the live girl. I also think the murderer sold real estate or something, but this was many years ago so take that with a grain of salt.

Sydney wrote: "In 4th Grade, which was 2006-7 for me, my teacher had us read this book. Basically it was about this girl who moved into this house and had like a way younger brother, and there was a girl who live..."
I also remember that the man was trying to forge the ghost's mom's signature over important documents, no idea if that adds anything but he was trying to take over the house or something like that

It sounds like The Ghost of Fossil Glen by Cynthia C. DeFelice. It makes sense that you would have read it in school since it won a LOT of awards. Particularly the Texas Bluebonnet which is chosen by students.

Thank you so much! That's it!