Thanks for your posting. My daughter will be 3 in a few days and we are struggling with the same problem. She won't let anyone strange get close to her, or touch her, forget it! She didn't even want to go see uncle Peter (her godfather) the other day. I had to force her up the stairs to his house and then she'd keep saying "he won't look at me" and then she'd look at him to see what he's doing and turn her head away. She's now doing the same thing to her godmother (who lives in the house next to ours). Two days ago, she brought some books for my girl and my daughter just freaked, started running around the driveway calling "Papa, papa, I want my Papa." She then ran to my husband. I felt almost embarrassed and the godmother was totally shocked. The problem we have is that I'm due to have a baby any day and we have noone to leave her with except her godmother, so this will be interesting. Anyway, as others have said here, I hope it's just a phase, so don't worry. Try to support your son and be patient. And I will try to do the same with my girl...:o)
Best of luck. I'm so glad to hear I'm not the only one with this issue because I was starting to wonder whether I should take her for an evaluation.