my 10 year old has had a fever for 6 days now andwas complaining about pain in left hip/buttocks area. I took him to the ER, they did blood work, x-ray, sonogram and even an MRI and found nothing. Last time i took his temp, the fever had spiked to 104. I am really concern, how could anyone have a fever for 6 days with nothing work? Doctors say to let it run it course, but i am very worried.