Does That REALLY Hurt?

Every time I take my son to OT I learn something new from his wonderful therapist.  I have a 4 year old son who hates getting his hair cut, washed or even dried after a bath.  When I was drying his hair the other day, he was crying and saying, "ow, ow, ow" as he does everytime I dry his hair.  I stopped and turned his face to look at mine and said, "Does that REALLY hurt?"  He cried, "Yes!"  So I talked to the therapist and she told me that some kids are VERY sensitive and if their hair is rubbed so that it goes against the grain (their hair follicles going in the opposite direction) it can cause them pain.  So I tried it and by golly, he was okay as long as I was rubbing his hair in the right direction.