My 6 yr old grandson has had a high fever for the last 3 days. (103.1 highest - 99.2 lowest) Tylenol has been keeping it down to a low grade fever. Need to keep giving tylenol every 4 hours. Along with fever he has a head cold, stuffy nose, diarrhea and vomiting. The vomiting has stopped. The head ache comes and goes. The diarrhea has just started. A slight rash on his buttocks has now appeared. He had a cool bath today which helped him feel better. Any idea what he may be fighting? I plan on taking to his doctor tomorrow if these symptoms persist.