Marie-Thérèse was the daughter of Edward von Solms, consul of Württemberg in Paris, and Olympe Adrienne Bentzon. She was born in the family house, owned by her grandparents. She had a brother, from whom we know nothing. Her grandmother, a woman she never mentions in her letters except to say she was a "witty and sound Parisian" was at that time remarried to the Marquis de Vitry, an old French aristocrat, born before the French Revolution, who used to tell her story about this era.