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The Year of Isabella I of Castile - Joan of Portugal, A Queen in an impossible situation (Part four) - History of Royal Women
While at Alaejos, Joan fell in love with Archbishop Alonso de Fonseca y Ulloa's nephew, Pedro de Castilla y Fonseca. Pedro was a descendant of King Peter of Castile through his illegitimate son, Diego. He was ten years younger than her, and Joan became pregnant.
Moniek Bloks