DS - the annoying boy - had started biting his nails (yuk).
On one of his fingers there is what looks like a cluster of 3 small cold sores (finger nail side, just under the cuticle).
Any ideas - could it be a cold sore? It's been there a couple of weeks and he says it's not sore (although he also says he's not biting his nails - they must be shrinking then).