My son (4) has two small sores under his chin and a few marks on his neck. It isn't hand foot mouth, it isn't 5th or 6th disease, or chicken pox. He has no sores in his mouth or anywhere else. What is it? Just fyi he has autism and sensory issues and licks and sucks everything (including my MIL's garbage can), and is non-verbal so I don't know if they hurt, although he has been a little screechy lately.