My mother is having teriible cough after recovering from fever(infection) & cough. now my daughter also caught same fever & cough. fever has gone but ?

Contagious illness: This is a common illness pattern. Upper respiratory tract viruses enter & trigger a body response (fever). They leave behind injury to cells lining the respiratory tract that trigger cough. The cough remains for days or weeks after the body has eliminated the virus. These are often spread in saliva or airborne droplets. Those who have not had that virus are susceptible.