Born in 1918, the eldest child and son of Carlos Montez Champalimaud (Peso da Régua, Godim, 13 November 1877 – Cascais, 4 May 1937), a Military Doctor, Lord of the ancestral home of Quinta do Cotto in the Douro region (great-great-grandson in female line of French Paul Joseph Champalimaud, seigneur de Nussane, who came to Portugal and here married Clara Maria de Sousa Lira e Castro), and wife (m. Lisbon, 2 June 1917) Ana de Araújo de Sommer (Lisbon, 23 April 1885 – ?) (great-granddaughter in male line of German Franz Joseph Freiherr von Sommer and wife Klara Werlein von Ascheberg, who came to Portugal during the Liberal Wars).