K.G.
I am having the Same problem but with a 2 yr old. I went to the doctor about something else and decided to ask him about it. He told me since he was so young that there not doing it cause there nervious or its a habbit but because there curious of new things. He told me theres something called nail no bite or something to that effect and you can get it where ever nail polish is sold or ask the Pharmacy about it!I guess you put it on 3 times a day! Let me know if it works!