[Dale] and his sister [Lillian] were twins. Still, they did n't look very much alike. [Lillian] was playing in the sandbox with her brother [Wayne].
('Dale', 'Wayne')
[Dale] and his sister [Lillian] were twins. Still, they did n't look very much alike. [Lillian] was playing in the sandbox with her brother [Wayne].
[{('Dale', 'brother', 'Wayne'): [('Dale', 'sister', 'Lillian'), ('Lillian', 'brother', 'Wayne')]}]
['sister', 'brother']