William's son Robert, still allied with the French king, appears to have been active in stirring up trouble, enough so that William led an expedition against the French Vexin in July 1087.
Vilhelms son Robert, som fortfarande var allierad med den franske kungen Filip I ställde till problem, vilket fick Vilhelm att leda ett fälttåg mot franska Vexin i juli 1087.