story: [Nancy] took her younger sister [Crystal] to the carnival last weekend. [Crystal] is weary of her son [Mark]'s behaviour. He is often in trouble at school. [Crystal] took her son [David] to the park for the afternoon.
query: ('Mark', 'Nancy')
clean_story: [Crystal] is weary of her son [Mark]'s behaviour. He is often in trouble at school. [Nancy] took her younger sister [Crystal] to the carnival last weekend.
proof_state: [{('Mark', 'aunt', 'Nancy'): [('Mark', 'mother', 'Crystal'), ('Crystal', 'sister', 'Nancy')]}]