Thrush? The beginning of an apthous mouth ulcer? Possible hand foot and mouth or some other coxsackie virus? It's hard to tell without looking, but if it's not causing her any discomfort, that is a good sign.
Weeell... nurse clinic was closed for a few days anyway. But then, it disappeared! Can kinda see an 'edge' of skin around where it was, so guess it must have been some kind of blister? So cancelled doc cause was going to be hard to get over there anyway and he still seems fine.
My best guess is that he bit his tongue really hard and there was a blister... seems really strange to me, but no other symptoms at all.
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