story: [Crystal] sat anxiously in the airport terminal, waiting to see her son [Bernard] walk through the gate. [Crystal] and her sister [Minnie] are the only children in their family. [Crystal] took her son [David] to the mall to shop for school clothes.
query: ('Minnie', 'David')
clean_story: [Crystal] and her sister [Minnie] are the only children in their family. [Crystal] took her son [David] to the mall to shop for school clothes.
proof_state: [{('Minnie', 'nephew', 'David'): [('Minnie', 'sister', 'Crystal'), ('Crystal', 'son', 'David')]}]