[Kevin] asked his father, [Antonio], to help him with his math homework. [Antonio] could n't, because he was lousy at math himself. [Shantel]'s son, [Robert], never got along with [Shantel]'s other son, [Antonio]. [Tracy] has been waiting around all day for her son, [Kevin].
('Tracy', 'Robert')
[Tracy] has been waiting around all day for her son, [Kevin]. [Kevin] asked his father, [Antonio], to help him with his math homework. [Antonio] could n't, because he was lousy at math himself. [Shantel]'s son, [Robert], never got along with [Shantel]'s other son, [Antonio].
[{('Tracy', 'brother', 'Robert'): [('Tracy', 'son', 'Kevin'), ('Kevin', 'uncle', 'Robert')]}, {('Kevin', 'uncle', 'Robert'): [('Kevin', 'father', 'Antonio'), ('Antonio', 'brother', 'Robert')]}, {('Antonio', 'brother', 'Robert'): [('Antonio', 'mother', 'Shantel'), ('Shantel', 'son', 'Robert')]}]
['son', 'father', 'mother', 'son']