He was born in Lisbon, Sagrado Coração de Jesus. Luis" father was João Teotónio Pereira, Junior. (Lisbon, 1869 - Lisbon, São Domingos de Benfica, 1948), Administrator of the Companhia de Seguros Fidelidade, and his mother Virgínia Hermann von Boetischer (Lisbon, Santa Engrácia, 1871 - Lisbon, 1969).
Their children were Luis" younger brother, Pedro Teotónio Pereira, also a Politician and a Diplomat. He was a Deputy to the Assembleia Nacional, a Procurator to the Corporative Chamber and a Mayor of the Municipal Chamber of Almada during the Estado Novo and the government of António de Oliveira Salazar, like his father Administrator of the Companhia de Seguros Fidelidade, President of the Grémio de Exportadores de Vinhos e dos Exportadores de Azeite, Grand Officer of the Order of the Industrial Merit.
