Help me find a book/story?

[MikeC]

So I remember a short story from this anthology book I read years ago, but I can't remember the title or the book it's from. I seem to recall the plot fairly well, though. Maybe some of you guys remember!

It started with some girl and her father moving in next to a girl and her brother. They all get along fairly well, but when the girl and her brother visit one day, the new girl turns out to be some kind of monster, her father was dead the whole time, the brother dies, and then the girl probably dies. Does that ring any bells? Not knowing is driving me absolutely nuts.

Thanks!