[David]'s son, [Michael], came over to her house for dinner. [Johnson], [Michael]'s brother, came too. [David] loves playing chess her son. His name is [Bobby].
('Bobby', 'Johnson')
[David] loves playing chess her son. His name is [Bobby]. [David]'s son, [Michael], came over to her house for dinner. [Johnson], [Michael]'s brother, came too.
[{('Bobby', 'brother', 'Johnson'): [('Bobby', 'brother', 'Michael'), ('Michael', 'brother', 'Johnson')]}, {('Bobby', 'brother', 'Michael'): [('Bobby', 'mother', 'David'), ('David', 'son', 'Michael')]}]
['mother', 'son', 'brother']