Megastar Amitabh Bachchan, son Abhishek Bachchan, daughter-in-law Aishwarya Rai Bachchan and granddaughter Aaradhya Bachchan are responding well to the treatment to COVID-19, hospital sources said on Saturday. Amitabh, 77, and Abhishek, 44, are in the isolation ward of Nanavati hospital since July 11