ds1 is 2.2yrs. On and off I have noticed strange circles appearing on his tongue. He has three at the moment one the size of 5p and the others a 2p. They go from the top, round the side to underneath and are white round the edge and get darker to the inside. Just looks rather odd. He would tell me if he was uncomfortable, or they bothered him so I am not worried..... just wondering..... Any ideas what they are????