[Amy] talks to her son [Glen] every day. [Mary] was celebrating her birthday with her mother [Amy].
('Mary', 'Glen')
[Mary] was celebrating her birthday with her mother [Amy]. [Amy] talks to her son [Glen] every day.
[{('Mary', 'brother', 'Glen'): [('Mary', 'mother', 'Amy'), ('Amy', 'son', 'Glen')]}]
['mother', 'son']