[Pedro]'s father, [Harold], bought him some ice cream. [Shantel]'s son [Antonio] and daughter [Tracy] helped [Antonio]'s father [Harold] paint his house.
('Pedro', 'Tracy')
[Pedro]'s father, [Harold], bought him some ice cream. [Shantel]'s son [Antonio] and daughter [Tracy] helped [Antonio]'s father [Harold] paint his house.
[{('Pedro', 'sister', 'Tracy'): [('Pedro', 'mother', 'Shantel'), ('Shantel', 'daughter', 'Tracy')]}, {('Pedro', 'mother', 'Shantel'): [('Pedro', 'brother', 'Antonio'), ('Antonio', 'mother', 'Shantel')]}, {('Pedro', 'brother', 'Antonio'): [('Pedro', 'father', 'Harold'), ('Harold', 'son', 'Antonio')]}]
['father', 'son', 'mother', 'daughter']