My wife is at home with my son. The biggest problem that we have is that he pinches us (or even himself!) non-stop. I don't understand why this is happening. The worst is that he does this to himself and then others. It's as if he comes in contact with others and then immediately starts pinching.
Is this due to poor communication on our part? How can I teach him that this hurts and it's not acceptable behavior?
[UPDATE]
He usually pinches himself when he's really upset. When he pinches us we say that what he's doing is bad and that it hurts. The pinching started about 1 year ago, but only recently became much more frequent. In terms of development, he reached all of his milestones normally.