William IX1153 - 1156 Born Mon, 17 August 1153 Died Sun, 2 December 1156 Wallingford Castle, Wallingford Buried Reading Abbey, Reading Details Parents Count of Poitiers William Lived 3 years, 3 months, 15 days father Henry II 1133 - 1189 mother Eleanor of Aquitaine 1122 - 1204 Siblings Brother Henry the Young King 1155 - 1183 Sister Matilda of England 1156 - 1189 Brother Richard I 1157 - 1199 Brother Geoffrey II 1158 - 1186 Sister Eleanor of England 1161 - 1214 Sister Joan of England 1165 - 1199 Brother John 1166 - 1216