Son of Colonel the Hon. Sir Ernest Lucas Guest, K.B.E., C.M.G., C.V.O., and Lady Edith May Guest, of Salisbury, Southern Rhodesia. Was granted a Rhodes Scholarship at Trinity College, Oxford. On Ruzawi Preparatory School War Memorial, near Marandellas, Rhodesia. Remembered on Diocesan College Roll of Honour. He attended Diocesan College 1933-37. His uncle (WW1) and twin brother (WW2) also died in service