Who were Jean Le Rond d’Alembert’s biological parents?

Jean Le Rond d’Alembert was the illegitimate son of the French author and literary patroness Claudine-Alexandrine Guérin de Tencin and her lover, the chevalier Destouches-Canon.12

Following his birth in 1717, d’Alembert was abandoned on the steps of the Parisian church of Saint-Jean-le-Rond. Although Mme de Tencin never recognized him as her son, the chevalier Destouches eventually sought out the child and provided for his upbringing by entrusting him to a glazier’s wife, whom d’Alembert regarded as his mother. Destouches also left his son an annuity, though he never publicly disclosed his identity as the boy's father.1