You are right, hand foot and mouth is viral. You should bring them both to the ped. to be on the safe side. I found that tylenol and or motrin and lots of ice pops and ice cream really helped my daghter through it. She was 3 at the time. This virus is very common in the summer and fall but that depends on your climate also. I am in NY so summer and fall it is for me. It does last a bit though. I beleive she had the sores for about 1 week. But as long they are hydrated they should be alright. If they want to eat then great but don't force them. Also change the tooth brushes you use and make sure they wash thier hands very frequently. Some sort of allergy med is good too. it will make them drowsy though. I would ask the doc if/what they suggest is a good allergy med to give them. My older one I gave claritin or benedryl. Good luck! Keep your head up it will blow over soon.