My son who is just over a year old has developed a rash on his kneees, and a little on his thigh. Its about a soda can (the circle part) sized rash, little red raised dots that feel rough and almost sand-paperish. Theres no white head on them, they dont ooze or seem to itch for him. And I noticed that outside of that one circluar area there are 5 or 6 dots that are all on their own on his legs. theres no fever or any other type of symptoms beyond this. Please advise on what this could be?