[Harold] made a grilled cheese for his son [Pedro]. [Pedro]'s brother [Antonio] ate a salad. [Louis] took his daughter [Nettie] to see her grandfather [Harold] after school yesterday.
('Louis', 'Antonio')
[Louis] took his daughter [Nettie] to see her grandfather [Harold] after school yesterday. [Harold] made a grilled cheese for his son [Pedro]. [Pedro]'s brother [Antonio] ate a salad.
[{('Louis', 'brother', 'Antonio'): [('Louis', 'father', 'Harold'), ('Harold', 'son', 'Antonio')]}, {('Harold', 'son', 'Antonio'): [('Harold', 'son', 'Pedro'), ('Pedro', 'brother', 'Antonio')]}, {('Louis', 'father', 'Harold'): [('Louis', 'daughter', 'Nettie'), ('Nettie', 'grandfather', 'Harold')]}]
['daughter', 'grandfather', 'son', 'brother']