بلدوين الرابع
In the Holy Land, Philip hoped to take part in a planned invasion of Egypt, for which purpose the crusaders had allied with the Byzantine Empire. A Byzantine fleet of 150 galleys was waiting at Acre when Philip arrived on 2 August. Philip had other plans, however. He and King Baldwin IV of Jerusalem were first cousins, sharing a grandfather, King Fulk, whose daughter from his first marriage, Sibylla of Anjou, was Philip's mother. Baldwin IV was a leper and childless, and offered Philip the regency of the Kingdom of Jerusalem as his closest male relative currently present there. Philip refused both this and the command of the army of the kingdom, saying he was there only as a pilgrim. Instead Baldwin appointed Raynald of Châtillon, to whom Philip would act as an assistant. As William of Tyre says, "this being the situation, the count at last revealed the secret thought of his mind and did not try to conceal to what end all his plans were." He had come to have his own vassals married to his cousins, Baldwin's sister Sibylla and half-sister Isabella.