[Lillian] called her brother, [Nicholas], up to see how he was doing after surgery. [Lillian] called [Nancy], her sister, to see if she wanted to go out to eat.
('Nancy', 'Nicholas')
[Lillian] called [Nancy], her sister, to see if she wanted to go out to eat. [Lillian] called her brother, [Nicholas], up to see how he was doing after surgery.
[{('Nancy', 'brother', 'Nicholas'): [('Nancy', 'sister', 'Lillian'), ('Lillian', 'brother', 'Nicholas')]}]
['sister', 'brother']