DS (5) has woken up this morning with a big swollen red/purple looking lip on one side. On closer inspection it appears to have a yellowish section in the midddle. He says it's sore but it doesn't seem to be bothering him much. From googling it appears it may be a cold sore although I didn't think they just appeared out of the blue! Anyway, this is the first experience I've ever had with a cold sore as me, DH or Dd have never had one. Obviously I've told him not to touch it but other than that is there anything else I need to do?