My son was recently ill, he has had an ear and throat virus which caused him to have a high fever, coughing, diarrhoea etc..

He doesn't have symptoms now only abit of a cough but last night after bathing him i have noticed a red rash on his back, belly, feet and a tiny bit on his face, I thought it might be from the throat spray the GP has prescribed him but I didn't give him any spray since yesterday afternoon and this rash got more noticeable, abit more red and in more places on his body, should i be worried about this rash or is this normal for babies? Im unsure on what to do and need some advise please

Thank you in advance