Ok, I read this earlier in the summer, but the book I'm reading now is a bit long and I wanted to give you something while I'm still working on it. I'm also going to do exactly what everybody who reviewed this book before me did and give away something that's revealed about a third of the way in, because the cover text reveals it, too.
Rosemary starts this story as she is trying to navigate her college years, attempting to find her place in the world where she has never fit in outside her family, and dealing with the dysfunction of her family which has come apart since her sister, Fern, mysteriously went away when she and Rosemary were both five. What we find out as the book goes on is that Fern is a chimpanzee.
Although this book is not SF exactly, I think it is a wonderful book for fans of soft SF. Fundamentally it is a book that uses a non-human character to examine what it means to be human and what it means to be a family, which SF has been doing since Cyrano de Bergerac wrote a book about going to the moon centuries before anybody invented a name for the genre. (It's also the best new novel about a human family raising a chimp that I read this summer. Surprisingly, there is more than one entry in that category.) I think it would also do well among fans of "women's lives and relationships," as the book is focused not only on Rosemary's relationship with her sister but also her parents, her brother on the lam, and her troublemaking roommate Harlow.
I brought a couple of books back from the American Library Association this summer that belonged to series I already follow, but this was by far the best out of those I've gotten to at this point that was brand new to me.
Overall Grade: A+