Aiyoh, underweight baby memang worry sia, I understand lah. Few of my mum friends also went through this, important to follow doctor's advice on the TB screening and vaccines because underweight babies kena monitor closely untuk growth and health risks. Boleh ask your doc too if need any feeding tips or supplements to help baby gain weight, sometimes ada certain tricks like feeding schedule or formula changes yang boleh help. Hang in there, mami, many babies catch up quickly once they get the right support!