[Robert] bought a book for his father [Harold]. [Nettie] gave her brother [Paul] a new sweater for Christmas. [Paul] asked his father [Louis] if they could go to the library. [Louis]'s father [Harold] was there already, waiting for them.
('Nettie', 'Robert')
[Nettie] gave her brother [Paul] a new sweater for Christmas. [Paul] asked his father [Louis] if they could go to the library. [Louis]'s father [Harold] was there already, waiting for them. [Robert] bought a book for his father [Harold].
[{('Nettie', 'uncle', 'Robert'): [('Nettie', 'father', 'Louis'), ('Louis', 'brother', 'Robert')]}, {('Louis', 'brother', 'Robert'): [('Louis', 'father', 'Harold'), ('Harold', 'son', 'Robert')]}, {('Nettie', 'father', 'Louis'): [('Nettie', 'brother', 'Paul'), ('Paul', 'father', 'Louis')]}]
['brother', 'father', 'father', 'son']