I got this out of the Horror section but until late in the story I didn't know if it was going to turn out to be supernatural or human monsters. That would be telling though. Part of the fun is trying to work out that point.
The story had a lot of action once it got going. The first half is basically character development before things heat up. There was some foreshadowing that never really went anywhere and a few things didn't quite fit together, but I enjoyed the read. The only real niggle was one of the explanations near the end that was the reverse of known science. Let's just say that inbreeding tends to produce mutations and that's one of those everybody knows that facts.
There was also too little explanation of how the guardians managed to get close to the family without ever being seen. I was a little disappointed by the ending, but at least it tied everything up. The writing itself was good and made it hard to stop in the later chapters. I guess sometimes you just have to enjoy a read for what it is and not worry about realism.