Congrès celtique
In 1905 Sir Harry married Alida Luisa, daughter of Sir Robert Harvey, by whom he had one son and one daughter. Created a Dame Commander of the DBE in 1929, Lady Brittain was a harpist, made member of the Celtic Congress (1933) and a Bard of the Gorsedd of Cornwall (Gorseth Kernow), using the name "Colom Wyn" or "White Dove". She died in 1943.