# coding=utf-8 name = 'grandparent/2' slug = 'the grandparent relation' description = '''\
grandparent(?P, ?C): P is a grandparent of C.
grandparent(?P, ?C)
P
C
?- grandparent(tina, X). X = vanessa ; X = patricia. ?- grandparent(tina, vanessa). true.