[Jeff]'s wife [Heidi] and his mother [Nancy] went tanning on the beach last weekend.
('Heidi', 'Nancy')
[Jeff]'s wife [Heidi] and his mother [Nancy] went tanning on the beach last weekend.
[{('Heidi', 'mother-in-law', 'Nancy'): [('Heidi', 'husband', 'Jeff'), ('Jeff', 'mother', 'Nancy')]}]
['husband', 'mother']