[Stephanie] is [Mary]'s daughter, they spend time together. [David] is [Stephanie]'s son who goes to school.
('Mary', 'David')
[Stephanie] is [Mary]'s daughter, they spend time together. [David] is [Stephanie]'s son who goes to school.
[{('Mary', 'grandson', 'David'): [('Mary', 'daughter', 'Stephanie'), ('Stephanie', 'son', 'David')]}]