'Letters from Parents from 1930s and Sewells Orchard to 1958 USA Commonwealth File entitled 'Letters from Parents from 1930s and Sewells Orchard to 1958 USA Commonwealth'. In the file is a collection of letters to Mary from her parents. Sewells Orchard is their address in Welwyn and 'USA Commonwealth' refers to the year David and Mary Medd spent working for the Commonwealth Fund in the USA. 1938-1958