CREATE TABLE table_name_70 (caps INTEGER, club_province VARCHAR(255), date_of_birth__age_ VARCHAR(255))
Which Caps is the lowest one that has a Club/province of ospreys, and a Date of Birth (Age) of 19 september 1985?
    
SQL: SELECT MIN(caps) FROM table_name_70 WHERE club_province = "ospreys" AND date_of_birth__age_ = "19 september 1985"