_David ROBERTSON ____+ | _William ROBERTSON __| | | | |_____________________ | _William ROBERTSON __| | | | | _____________________ | | | | |_Isabel PETRIE ______| | | | |_____________________ | | |--Jean ROBERTSON | | _____________________ | | | _____________________| | | | | | |_____________________ | | |_Margaret MITCHELL __| | | _____________________ | | |_____________________| | |_____________________