F is for Family (book is about a family or family relationships)

I started reading when I got home from work yesterday. It was such a fascinating story that I kept reading until I finished. The setting is a city that is built up towards the sky, where only the rich live. The action takes place further down. Much further down.
I only picked the book because it fit in my keyword challenge. The author was a new one for me and I'm sooooo glad I took a chance on it. This is one book where the interesting concept was fully delivered in the story.