just washing ds1's hair, who is just 9 and have noticed on one side of his head, the hair has receded right back about 2 inches from forehead to eaar backwards and he just has fluffy hair where it used to be. please give me some idea as to why as its freaking me out as no idea why. his hair otherwise is very thick, he doesnt play with his hair and doesnt use any weird lotions or potions on it.