I originally gave this a 7 out of ten, but after thinking about it all day, I felt angry enough to change my vote to a 3 and leave an annoyed review.
I really enjoyed almost all of the movie. Loved up couple have a baby, decide to move away to the country for some quiet time. The husband is a musician so he wants some time to write and the wife wants to do up the house and raise her kid away from the busy city. Unfortunately baby wont sleep, which means parents don't sleep, resulting in sleep deprivation. The couple start arguing, they forget what they're doing, everything is not good. Plus there is some really creepy stuff going on the house, which just adds to their increasing madness.
I liked the slow decline into madness as the couple suffer more and more sleepless nights. I liked how this was further exacerbated by what was going on in their house. However, the conclusion and explanation, i.e. the ending, was utterly ridiculous and infuriating. It totally ruined the film for me and it didn't make any sense. The whole movie was rendered mute by the stupid ending and I feel cheated.
To summarise: Good film overall, creepy, engaging but sadly destroyed by idiotic ending.