I have started giving my 11 month baby buffalo milk with water on 50: 50 ratio from 4 months. But since then he has been getting lot of cough and sometimes he even vomits at night while coughing. I give him bottle with 120 ml milk twice during the night and once I feed him. During the day I give him aata soup, banana, roti, rice, etc. Of whatever we cook at home. Is milk the cause of his cough? If yes, what milk would be best suited for him then?