What Is The Treatment For Flesh Colored Bumps On Thighs And Knees?

My 7 year old son has had these tiny flesh colored bumps on his thighs and knees. He has more on his left leg and only a few on his right leg. They do itch a little but when he scratches he scratches his entire thigh are, not just where the pumps are. They seem to be spreading to his knee but only on that left side. It does not hinder him at all and he doesn't complain unless I ask him about it. I just started applying aloe vera to it.