[David] took her son [Michael] to the mall to shop for school clothes. [Francisco] went to the grocery store for his brother [Joshua], because he broke his leg. [Joshua], who is [Michael]'s uncle, got [Michael] the video game he wanted for his birthday.
('David', 'Francisco')
[David] took her son [Michael] to the mall to shop for school clothes. [Joshua], who is [Michael]'s uncle, got [Michael] the video game he wanted for his birthday. [Francisco] went to the grocery store for his brother [Joshua], because he broke his leg.
[{('David', 'brother', 'Francisco'): [('David', 'brother', 'Joshua'), ('Joshua', 'brother', 'Francisco')]}, {('David', 'brother', 'Joshua'): [('David', 'son', 'Michael'), ('Michael', 'uncle', 'Joshua')]}]
['son', 'uncle', 'brother']