[Amy] took her son, [Glen], to the movie theater for his birthday. [Dale] took his sister [Amy] to the movies with him to see the new Star Wars film.
('Dale', 'Glen')
[Dale] took his sister [Amy] to the movies with him to see the new Star Wars film. [Amy] took her son, [Glen], to the movie theater for his birthday.
[{('Dale', 'nephew', 'Glen'): [('Dale', 'sister', 'Amy'), ('Amy', 'son', 'Glen')]}]
['sister', 'son']