 She was also a volunteer nurse with the Medical Auxiliary Service.After the fall of Singapore in 1942, the Choys set up a canteen at the Tan Tock Seng Hospital, after all the patients and doctors had been moved from the Miyako Hospital (former Woodbridge Hospital), where they soon started a regular ambulance run for British civilian internees.The couple helped prisoners-of-war interned in Changi Prison by passing to them cash and parcels containing fresh clothing, medicine and letters during their deliveries.