William I of Sicily 12th-century king of Sicily (1126–1166) Parents Elvira of Leon Roger II of Sicily Children William II of Sicily Roger IV, Duke of Apulia Matina di Sicilia Henry, Prince of Capua Robert III, Prince of Capua Siblings Tancred, Prince of Bari Alfonso of Hauteville Roger III, Duke of Apulia Simon, Prince of Taranto Tancred, King of Sicily Costanza I of Sicily Adelicia of Sicilia Partners Margaret of Navarre
