L.D.
Hi, my name is L., I have 4 childern they are grown now but my oldest did the same thing when she was about that age and I had a friend who also had this happening with her 3 yr old daughter. Well, my doctor said it was a normal behavior for a child her age. Because at that age they start to have sensations and are curiouse. I asked him what to do about it and he said not to scold her but to try to distract her when she does it and to explain to her not to do it. We took his advice and after a little while she had stopped. Does she go to a sitter if so she may have seen another child do it and it peaked her curiousity. That was how my friends little girl started, she saw her little cousin do it. My friend did the same thing. I hope i was of some help...beleive me it is not abnormal. Goog luck, L.