My son is 16 months old. He started with a fever (100.2 - 100.4) on Monday evening. On Tuesday, when I took him to the doctor she said he breathing heavy and took chest x-ray . She couldnt conclusively say it was clean, so she asked us to start him on antibiotics . Started the course Tuesday morning. We gave him Ibprofen for fever on Tues morning, before bed, Wed morning and Wed before bed. He was fine on Thursday, though he started getting runny nose and occasional cough. Friday afternoon the cough got worse and he started breathing really fast and heavy and temperature again went to 100.4. We went in to ER, they did the x-ray again and said no signs of pneumonia . They asked us to keep watching him... his fever is still there, just gave Ibprofen... Any idea what is going on?