[Martha] and her son [Robert] went to the zoo and then out to dinner yesterday. [Roy] took his grandson [Robert] to the store to buy some new books.
('Martha', 'Roy')
[Martha] and her son [Robert] went to the zoo and then out to dinner yesterday. [Roy] took his grandson [Robert] to the store to buy some new books.
[{('Martha', 'father', 'Roy'): [('Martha', 'son', 'Robert'), ('Robert', 'grandfather', 'Roy')]}]