Gwendoline Courtney was born near Southampton, the younger daughter of Edwin Courtney, an antiques dealer, and Joanna nee Potter. Although there seem to have been no professional writers among her forebears, Arthur Mee was a distant cousin and among her first cousins was Phyllis Norris, who wrote 8 girls books. Gwendoline failed to matriculate because of ill health and may have trained as a secretary; she seems to have worked for some time in her father's office. During the second world war she worked in Lord Goodman's office and prided herself on being the only civilian to work on Operation Overlord. She suffered an ear injury from a bomb blast that made noise hard to bear and later moved around a great deal.