[Michael] always looked up to his big brother [David] and wanted to be just like him. [Mary] wrote a nice letter to her grandson [David].
('Mary', 'Michael')
[Mary] wrote a nice letter to her grandson [David]. [Michael] always looked up to his big brother [David] and wanted to be just like him.
[{('Mary', 'grandson', 'Michael'): [('Mary', 'grandson', 'David'), ('David', 'brother', 'Michael')]}]