[Frances] took her granddaughter [Marie] to the mall. [Marie]'s dad [Hugh] was happy to have the house to himself. [Bobby] asked his father, [Hugh], to help him with his math homework. [Hugh] could n't, because he was lousy at math himself.
('Bobby', 'Frances')
[Bobby] asked his father, [Hugh], to help him with his math homework. [Hugh] could n't, because he was lousy at math himself. [Frances] took her granddaughter [Marie] to the mall. [Marie]'s dad [Hugh] was happy to have the house to himself.
[{('Bobby', 'grandmother', 'Frances'): [('Bobby', 'sister', 'Marie'), ('Marie', 'grandmother', 'Frances')]}, {('Bobby', 'sister', 'Marie'): [('Bobby', 'father', 'Hugh'), ('Hugh', 'daughter', 'Marie')]}]
['father', 'daughter', 'grandmother']