[Milton] took a vacation from his job to visit his mother [Amy] across the country for Mother's Day. [Amy] went out for pizza with her father [Clarence].
('Milton', 'Clarence')
[Milton] took a vacation from his job to visit his mother [Amy] across the country for Mother's Day. [Amy] went out for pizza with her father [Clarence].
[{('Milton', 'grandfather', 'Clarence'): [('Milton', 'mother', 'Amy'), ('Amy', 'father', 'Clarence')]}]
['mother', 'father']