Jean de Castille Son of Peter I of Castile (1355–1405) Parents Joan of Castro Peter of Castile Children Peter of Castile Constanza de Castilla Siblings Diego de Castilla Sancho de Castilla Constance of Castile, Duchess of Lancaster Isabella of Castile, Duchess of York María de Ayala Edward de Castilla Partners Elvira de Eril y Falcés