[Theresa] was playing in the sandbox with her brother [Nicholas]. [Nancy] and her brother [Nicholas] sat down together to clip coupons.
('Theresa', 'Nancy')
[Theresa] was playing in the sandbox with her brother [Nicholas]. [Nancy] and her brother [Nicholas] sat down together to clip coupons.
[{('Theresa', 'sister', 'Nancy'): [('Theresa', 'brother', 'Nicholas'), ('Nicholas', 'sister', 'Nancy')]}]
['brother', 'sister']