I enjoyed this one, a werewolf story from a new point of view. That poor kid!
What really bothered me was the mother leaving the child behind. To me she's the real villain of the story. Perhaps part of it is that I assumed that the father became a werewolf by being bitten by a werewolf, which is the usual route. With this assumption, the trait is not hereditary, and so her leaving of the son is even worse, and is even probably condemning her son to the exact same fate--because a child is bound to make a mistake and get bitten, which of course is what happened. Even if it were hereditary, she is a terrible person for leaving him. he isn't even showing signs of turning yet and she leaves. And if her son DOES start turning, then the house will have TWO werewolves with no one to restrain them, and dozens of deaths will be on her hands for abandoning them. Not only that, but if werewolves retain their human memories, then she could very well be a target for her transformed son.
And I'm a bit shocked that they hadn't thought up a food delivery system that didn't require opening the door all the way. Like a prison-style slot in the door, or maybe meat packages dropped down the laundry chute. If they'd had that the son wouldn't've been bitten.
I didn't, however, see the son's turning in of his father as too sudden. If it's the classical werewolf rules, his son will now be a werewolf too, and so he suddenly has much more incentive to think he'll end up like his father. In fact, if the father's first priority is ensuring the well-being of his child, he might even turn himself in. His own torture and dissection might be worthwhile if he knows it may provide insight that will save his son. And especially at that moment, while he's racked with guilt over biting the boy, he might be the most apt to turn himself in. On top of that, it would mean his son could have a normal life again (unless the change comes upon him).