Kings College Hospital is in Camberwell in South East London. The Patient Advice and Liaison Service is beside the foyer and their staff should be able to deal with any queries that you have (during office hours). There is a convenience store within 10 mins walk from hospital and a Sainsburys store within 20 mins walk. There are plenty of places to eat nearby (both sit-in and take away).
Birmingham Children’s Hospital is in Birmingham city centre and any staff on ward 8 will explain how to get to the Bullring. There is a Tesco and Sainsbury express shop within 10 mins walk from the hospital and many options for eating also.