We have a kitten who is 4 months old. After the first week of getting him, he started lunging at both of us for no reason. One minute he can be purring around you, and the next, he is attacking us. He bites down on our arms and holds on to it, and shouting at him does not make him stop. He bites so hard that it is very hard to pull him off. We have tried squirting water at him, and pulling him off and ignoring him, but he comes straight back at us! Has anyone got any suggestions on what we can do, and why he is acting this way?