story: [Casey] went to the wedding ceremony for his brother [Errol]. [Mark] and his brother [Alfred] were playing tag in the park. [Rose] is playing in the park with her son [Casey]. [Mark] is calling his sister [Rose] to let her know it's going to start to rain.
query: ('Mark', 'Errol')
clean_story: [Rose] is playing in the park with her son [Casey]. [Mark] is calling his sister [Rose] to let her know it's going to start to rain. [Casey] went to the wedding ceremony for his brother [Errol].
proof_state: [{('Mark', 'nephew', 'Errol'): [('Mark', 'sister', 'Rose'), ('Rose', 'son', 'Errol')]}, {('Rose', 'son', 'Errol'): [('Rose', 'son', 'Casey'), ('Casey', 'brother', 'Errol')]}]