[Nicholas] loved teaching his son, [Dennis], baseball. [Nicholas] and his sister [Nancy] stood in line at the fair.
('Nancy', 'Dennis')
[Nicholas] and his sister [Nancy] stood in line at the fair. [Nicholas] loved teaching his son, [Dennis], baseball.
[{('Nancy', 'nephew', 'Dennis'): [('Nancy', 'brother', 'Nicholas'), ('Nicholas', 'son', 'Dennis')]}]
['brother', 'son']