[Andrea] it going back to Boston to visit her sister [Janet] and her brother [Timothy].
('Timothy', 'Janet')
[Andrea] it going back to Boston to visit her sister [Janet] and her brother [Timothy].
[{('Timothy', 'sister', 'Janet'): [('Timothy', 'sister', 'Andrea'), ('Andrea', 'sister', 'Janet')]}]
['sister', 'sister']