[Rosetta] and her sister [Belva] went to the basketball game. [Rosetta] invited [Nicolas] to meet them there, since she is his sister.
('Nicolas', 'Belva')
[Rosetta] and her sister [Belva] went to the basketball game. [Rosetta] invited [Nicolas] to meet them there, since she is his sister.
[{('Nicolas', 'sister', 'Belva'): [('Nicolas', 'sister', 'Rosetta'), ('Rosetta', 'sister', 'Belva')]}]
['sister', 'sister']