 The son of that union, Prince Casimir Poniatowski (1897–1980), became the father of Michel by his 1920 marriage to Countess Anne de Caraman-Chimay (1901–1977), member of a Belgian princely family.Poniatowski attended the Cours Hattemer, a private school.He attended the ENA for finance and began his career in Morocco, later becoming a finance attaché in Washington, DC in 1956.