A lithopaedion, or stone-child, is a dead fetus, usually the result of a primary or secondary abdominal pregnancy, that has been retained by the mother and subsequently calcified. This paper describes the earliest known case of this phenomenon. It was discovered in 1582, at the autopsy of a 68-year-old woman in the French city of Sens, and described in a thesis by the physician Jean d'Ailleboust. The woman had carried her lithopaedion for 28 years. In this historical vignette, the lithopaedion of Sens is compared to later instances of this phenomenon. The ultimate fate of the lithopaedion specimen, which was widely traded throughout Europe in the 1600s before finally ending up in Copenhagen, is traced.