Thanks for posting your query at healthcaremagic. I am sorry to hear that your baby is not doing well. You have not indicated whether antibiotics had been given to him or whether they are still being given. Cough is generally caused due to a viral infection and has an allergic component alongwith. If antibiotics are given they also kill the beneficial bacteria and cause diarrhoea. It is more likely to be an antibiotic associated diarrhoea rather than a viral diarrhoea in this case. You can give him steam inhalation which will help in relieving the cough. After the course of antiobiotics are completed, the stool should gradually normalise. If I had a patient like this, I would give Enterogermina alongwith. In the meantime you should continue giving him proper diet and plenty of fluids to drink. Hope that I could resolve your query. Feel free to communicate back in case of further queries if any.