Hi, my son had what appeared to be a nasty purple bruise on the inside of his elbow when he got home from school, it definitely was not there the night before and I am sure he or I would have noticed it that morning (but cannot guarantee). It wouldn t blanch so was a bit concerned but no other symptoms so decided it was a bruise although no idea from what. Almost looked like tyre imprint with splatters around it. Still there at 8pm when he went to bed, 7am next morning it had completely vanished. Was about 4cms across at a guess. Any ideas?