story: [Carol] asked her mother [Sandra] if she could help her with college homework. [Sandra] was busy so she asked [Carol] to ask her sister [Lisa] instead. [Carol] was talking about food with her sister [Rose]. [Erik] loves his mother very much. Her name is [Lisa].
query: ('Erik', 'Sandra')
clean_story: [Erik] loves his mother very much. Her name is [Lisa]. [Carol] asked her mother [Sandra] if she could help her with college homework. [Sandra] was busy so she asked [Carol] to ask her sister [Lisa] instead.
proof_state: [{('Erik', 'grandmother', 'Sandra'): [('Erik', 'mother', 'Lisa'), ('Lisa', 'mother', 'Sandra')]}, {('Lisa', 'mother', 'Sandra'): [('Lisa', 'sister', 'Carol'), ('Carol', 'mother', 'Sandra')]}]