[Nancy] baked a cake for her son [Jeff]. [Kevin] was adopted kid. He discovered last week that [Nancy] is his mother.
('Kevin', 'Jeff')
[Kevin] was adopted kid. He discovered last week that [Nancy] is his mother. [Nancy] baked a cake for her son [Jeff].
[{('Kevin', 'brother', 'Jeff'): [('Kevin', 'mother', 'Nancy'), ('Nancy', 'son', 'Jeff')]}]
['mother', 'son']