[Charles] and his brother [Chris] went to the football game together. [Charles] and his sister [Pamela] stood in line at the fair. [Pamela]'s sister, [Martha], recently started acting.
('Martha', 'Chris')
[Pamela]'s sister, [Martha], recently started acting. [Charles] and his sister [Pamela] stood in line at the fair. [Charles] and his brother [Chris] went to the football game together.
[{('Martha', 'brother', 'Chris'): [('Martha', 'brother', 'Charles'), ('Charles', 'brother', 'Chris')]}, {('Martha', 'brother', 'Charles'): [('Martha', 'sister', 'Pamela'), ('Pamela', 'brother', 'Charles')]}]
['sister', 'brother', 'brother']