[Mary] kept picking on her sister [Jennifer]. [Jennifer] was so upset, she asked her brother [Dennis] for some help.
('Mary', 'Dennis')
[Mary] kept picking on her sister [Jennifer]. [Jennifer] was so upset, she asked her brother [Dennis] for some help.
[{('Mary', 'brother', 'Dennis'): [('Mary', 'sister', 'Jennifer'), ('Jennifer', 'brother', 'Dennis')]}]
['sister', 'brother']