name a office holder whose predecessor is henry petty-fitzmaurice and has son named edward stanley ?
SELECT DISTINCT var_uri where brack_open var_uri dbo_predecessor dbr_Henry_Petty-Fitzmaurice,_5th_Marquess_of_Lansdowne sep_dot var_uri dbo_child dbr_Edward_Stanley,_17th_Earl_of_Derby sep_dot var_uri a dbo_OfficeHolder brack_close