[Pamela] was playing in the sandbox with her brother [Charles]. [Charles] was delayed picking up his sister, [Martha], from class. Thankfully, [Lena]'s mom, [Martha], was already there.
('Pamela', 'Lena')
[Pamela] was playing in the sandbox with her brother [Charles]. [Charles] was delayed picking up his sister, [Martha], from class. Thankfully, [Lena]'s mom, [Martha], was already there.
[{('Pamela', 'mother', 'Lena'): [('Pamela', 'sister', 'Martha'), ('Martha', 'mother', 'Lena')]}, {('Pamela', 'sister', 'Martha'): [('Pamela', 'brother', 'Charles'), ('Charles', 'sister', 'Martha')]}]
['brother', 'sister', 'mother']