Such a thing is nigh on impossible. Especially in Medieval times. However, one could allow for the expansion of bothe the Kingdom of Sicily and the Angevin Empire.
Sicily's military contributions to the Crusader states would have been one mighty godsend, if Baldwin I of Jerusalem was able to completely get shot of the Armenian Princess Arda before he married Adelaide del Vasto, the mother of Roger II. Roger ruled and affluent and centralized state, and commanded a powerful navy. Even attempts to capture territory in North Africa were undertaken. As both Adelaide and Baldwin would have been too old to have any children together, then Roger of Sicily could have been Baldwin's legitimate heir, had the marriage been a more successful one. In this scenario, Roger would have had more of a reason to ship soldiers to assist the Crusader allies, and even assert something approaching a clear hierarchy of control among them, if only to cease their infighting. He could even use his relation with Prince Bohemond I to present himself as an alternative to Byzantine vassalage.
While the Angevin Empire was really a federation of autonomous realms that were ruled by the same family, and the Plantegenets had maternal links with William of Normandy through Matilda, the daughter of Henry I, the wife of Geoffrey V Count of Anjou, and mother of Henry II, they represented the height of Anglo-Norman territorial power. With the combined possession of England, Normandy, Brittany, Gascony, Anjou, Maine, Nantes, and Aquitaine (through Henry II's wife Eleanor), they held more land than the Capetian Kings of France, their feudal overlords. Imagine a united royal federation stretching over the British Isles, France, and the Low Countries!