[Leonard] and his brother [Richard] baked chocolate chip cookies for [Natasha], [Richard]'s sister. [Frances] is so proud of [Natasha] who is the sister of her grandson.
('Leonard', 'Frances')
[Leonard] and his brother [Richard] baked chocolate chip cookies for [Natasha], [Richard]'s sister. [Frances] is so proud of [Natasha] who is the sister of her grandson.
[{('Leonard', 'grandmother', 'Frances'): [('Leonard', 'sister', 'Natasha'), ('Natasha', 'grandmother', 'Frances')]}, {('Leonard', 'sister', 'Natasha'): [('Leonard', 'brother', 'Richard'), ('Richard', 'sister', 'Natasha')]}]
['brother', 'sister', 'grandmother']