_Richard de Clair ________ _Gilbert de Clair III_|_Amicia ( of Gloucester )_ _Richard de Clair IV_| | | _William Marshal _________ | |_Isabel Marshal ______|_Isabel fitz Gilbert _____ _Gilbert de Clair IV_| | | __________________________ | | _John de Lacy ________|__________________________ | |_Maud de Lacy _______| | | _Gilbert de L'Aigle ______ | |_Alice de L'Aigle ____|__________________________ | |--Margaret de Claire | | _John_____________________ | _Henry III____________|_Isabella of Agouleme_____ | _Edward I____________| | | | __________________________ | | |_Eleanor of Provence__|__________________________ |_Joan of Arce________| | __________________________ | ______________________|__________________________ |_Eleanor of Castile__| | __________________________ |______________________|__________________________