[Robert] brought home straight A's to his father [Harold]. [Pedro] brought home straight C's to his father [Harold]. [Nettie] loves to visit her Uncle [Pedro] on his farm. [Nettie] invited her father [Louis] to dinner.
('Louis', 'Robert')
[Nettie] invited her father [Louis] to dinner. [Nettie] loves to visit her Uncle [Pedro] on his farm. [Robert] brought home straight A's to his father [Harold]. [Pedro] brought home straight C's to his father [Harold].
[{('Louis', 'brother', 'Robert'): [('Louis', 'brother', 'Pedro'), ('Pedro', 'brother', 'Robert')]}, {('Pedro', 'brother', 'Robert'): [('Pedro', 'father', 'Harold'), ('Harold', 'son', 'Robert')]}, {('Louis', 'brother', 'Pedro'): [('Louis', 'daughter', 'Nettie'), ('Nettie', 'uncle', 'Pedro')]}]
['daughter', 'uncle', 'father', 'son']