[Mary] picked her granddaughter [Alberta] up from school Monday. [Alberta] 'brother [Carl] rode the bus home after school.
('Mary', 'Carl')
[Mary] picked her granddaughter [Alberta] up from school Monday. [Alberta] 'brother [Carl] rode the bus home after school.
[{('Mary', 'grandson', 'Carl'): [('Mary', 'granddaughter', 'Alberta'), ('Alberta', 'brother', 'Carl')]}]