[Emily] met her grandfather, [Clarence], for ice cream. [Michael] is going to the arcade with his sister, [Emily].
('Michael', 'Clarence')
[Michael] is going to the arcade with his sister, [Emily]. [Emily] met her grandfather, [Clarence], for ice cream.
[{('Michael', 'grandfather', 'Clarence'): [('Michael', 'sister', 'Emily'), ('Emily', 'grandfather', 'Clarence')]}]
['sister', 'grandfather']