my Ds is 11.5 months and in the past few weeks has started to stick his fingers down his throat. he does it until he gags and thn smiles at me. I have stopped reacting to it as initially i would say don't do that but i think that just made him do it more - hence the smile when he's done it. He doesn't make himself sick but i am worried about why he is doing it. Is this normal? Is it just a form of exploration?