story: [Nancy] and her husband, [Paul], went for a walk. [Robert], [Paul]'s son, tagged along. [Paul] is a man with a daughter named [Sabrina].
query: ('Nancy', 'Robert')
clean_story: [Nancy] and her husband, [Paul], went for a walk. [Robert], [Paul]'s son, tagged along.
proof_state: [{('Nancy', 'son', 'Robert'): [('Nancy', 'husband', 'Paul'), ('Paul', 'son', 'Robert')]}]