story: [Lisa] bought a nice gift for her son [Erik]. She bought an even more expensive gift for her daughter [Eustolia], however. [Peter] decided to take his son, [Erik], on a ski vacation. [Stacy] and his brother [Erik] are fighting again.
query: ('Peter', 'Eustolia')
clean_story: [Peter] decided to take his son, [Erik], on a ski vacation. [Lisa] bought a nice gift for her son [Erik]. She bought an even more expensive gift for her daughter [Eustolia], however.
proof_state: [{('Peter', 'daughter', 'Eustolia'): [('Peter', 'son', 'Erik'), ('Erik', 'sister', 'Eustolia')]}, {('Erik', 'sister', 'Eustolia'): [('Erik', 'mother', 'Lisa'), ('Lisa', 'daughter', 'Eustolia')]}]