Roseola?!?!?!?!?

What an interesting week this has been! Bradyn had been on antibiotics last week for a bad cold. Then Sat, night he started running a fever it went from 103.8-100.8 with tylenol and motrin. He threw up several times that night and next morning, but would act fine part of the time. He is still running a slight fever, but yesterday we noticed a fine, red rash on his back and stomach. Today it has spread to his face and some on his arms. Several people told me it sounds like roseola...