[Dennis] and his sister [Jennifer] took their father out to eat for his birthday. They had a great time. [Natalia] borrowed some money from her brother [Dennis].
('Natalia', 'Jennifer')
[Natalia] borrowed some money from her brother [Dennis]. [Dennis] and his sister [Jennifer] took their father out to eat for his birthday. They had a great time.
[{('Natalia', 'sister', 'Jennifer'): [('Natalia', 'brother', 'Dennis'), ('Dennis', 'sister', 'Jennifer')]}]
['brother', 'sister']