My DS has a big sore on his chin and a sort of spot/cold sore (has pus like a spot) near his lip. Initially I thought it was just really dried out skin from lots of spit,he seems to be quite dribbly at the moment and think maybe molars coming in(he is 2) but then the pus/white head formed and it also hasn't been helped at all by sudocreme or savlon. Any ideas?