story: [Otto]'s sister, [Crystal], participated in the dance contest. [Melissa] went on a vacation with her brother [Otto]. [Otto] is taking his son [William] out for coffee.
query: ('Melissa', 'Crystal')
clean_story: [Melissa] went on a vacation with her brother [Otto]. [Otto]'s sister, [Crystal], participated in the dance contest.
proof_state: [{('Melissa', 'sister', 'Crystal'): [('Melissa', 'brother', 'Otto'), ('Otto', 'sister', 'Crystal')]}]