This type of physical exuberance, while it is usually meant to be friendly, is often not welcome. It is often experienced as intrusive. He's receiving such feedback from others, and this ffedback will gradually take hold. You are doing what you can by way od helping your son understand the impact of his behavior. He's now at an age when such feedback begins to make sense, but he's only at the very beginning age for this to be so. Be patient and keep up your efforts. On the home front, in order to help him learn to respect personal space/boundaries, give him a brief time out when this occurs. The time out is not meant so much to be punitive, but to 'flag' his behavior as unacceptable and as something you expect him to learn to control. Also, place a sign or picture somewhere in his room where he will often see it. It will help him to develop a bit of 'observing ego' - i.e., the capacity to take a look at his own behavior. As he begins to ask himself "Is this a good idea?" before he touches people, he'll relax the behavior.
Your comments are a great help! I especially love the idea of using a picture to remind him. He had another "incident" just yesterday, after I left this message. He put a friend in a bear hug and I had to finally tell him to let go. He said "I was just giving him a hug!", but the poor other kid didn't know what to do. We have some work to do, but your ideas will definatly help!
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