DS is 25 months. He's been at nursery since he was 7 months old and was probably ill once every other month until November. Since November he has been ill virtually constantly. Chest infection, ear infection, hand foot and mouth, viral infection etc. I feel as if I am always giving him calpol&nurofen for a fever. Surely he shouldn't be ill this often after being at nursery for over a year. Could there be something underlying?