[Lillian] and [Amy] are sisters who have one brother named [Dale].
('Amy', 'Lillian')
[Lillian] and [Amy] are sisters who have one brother named [Dale].
[{('Amy', 'sister', 'Lillian'): [('Amy', 'brother', 'Dale'), ('Dale', 'sister', 'Lillian')]}]
['brother', 'sister']