[Cheryl] picked her sister, [Heather], up from the mall. [Heather] called her dad, [Pedro], when she got home to let him know where she was. [Beverly] borrowed some money from her brother [Robert]. [Cheryl] gave her Aunt [Beverly] a kiss.
('Pedro', 'Robert')
[Cheryl] picked her sister, [Heather], up from the mall. [Heather] called her dad, [Pedro], when she got home to let him know where she was. [Cheryl] gave her Aunt [Beverly] a kiss. [Beverly] borrowed some money from her brother [Robert].
[{('Pedro', 'brother', 'Robert'): [('Pedro', 'sister', 'Beverly'), ('Beverly', 'brother', 'Robert')]}, {('Pedro', 'sister', 'Beverly'): [('Pedro', 'daughter', 'Cheryl'), ('Cheryl', 'aunt', 'Beverly')]}, {('Pedro', 'daughter', 'Cheryl'): [('Pedro', 'daughter', 'Heather'), ('Heather', 'sister', 'Cheryl')]}]
['daughter', 'sister', 'aunt', 'brother']