[Rosetta] and her brother [Travis] played tennis together. [Rosetta]'s sister [Charlotte] has an injured leg and watched instead.
('Travis', 'Charlotte')
[Rosetta] and her brother [Travis] played tennis together. [Rosetta]'s sister [Charlotte] has an injured leg and watched instead.
[{('Travis', 'sister', 'Charlotte'): [('Travis', 'sister', 'Rosetta'), ('Rosetta', 'sister', 'Charlotte')]}]
['sister', 'sister']