Hi, On Monday Sept 17 My Granddaughter Who I 8

Hi, on Monday Sept 17 my granddaughter who I 8 months old received a vaccine for Hepatitis B and Pneumonia. On Friday Sept 21 her temperature of 104 and was taken to a hospital emergency room and my son was told to give his daughter liquid Tylenol to lower the fever. My son has been doing that since then, but her temperature today was 105 today so my son took her to their doctor who took blood and gave my son a prescription for an antibiotic, Is there anything else my sone can do to find out what is causing such a high temperature ?