I just noticed a blister on ds neck. Its just a little one. He also has a couple the same on his chest. Is this it?? Damn it. He is 3.5. Do I need to take him to the doctors? What supplies do I need if it is. Sorry he is Pfb and ive got no idea what I need to do. They have been going round at nursery so I presume it is. Meh.