Agatha of Normandy daughter of William the Conqueror and Matilda of Flanders (1061–1079) Parents William the Conqueror Matilda of Flanders Children Siblings Henry I of England Cecilia of Normandy Constance of Normandy William II of England Matilda of Normandy Alberta Richard of Normandy Robert Curthose Adela of Normandy Adeliza Partners Alfonso VI of León and Castile