Janet Teissier du Cros, née Grierson, was born in Aberdeen, Scotland, the youngest of five daughters in a prosperous academic family. She learned fluent French from governesses and was educated at St. George's School in Edinburgh. After musical studies in Vienna, she returned to Edinburgh, where she met François Teissier du Cros, an engineer and physicist from an old French Protestant family. The couple married in 1930 and lived at times in the south of France and in Scotland. Just before the outbreak of World War II, they returned to France with their young son so that her husband could join his army regiment. During the war, she did not know where her husband was or whether he was even alive (he was taken prisoner by the Germans and, after his release, joined the French Resistance), and keeping her children fed and warm in winter was a full-time job. However, they all survived, and afterwards Janet wrote a wartime memoir, Divided Loyalties: A Scotswoman in Occupied France, published in 1962. She did translation work and also wrote feature stories about France for the Glasgow Herald. During the 1950s, she did broadcasts on BBC Radio, notably in a regular slot on Woman's Hour. Later in life, she published another memoir called Cross Currents: A Childhood in Scotland (1997).