class Person(models.Model):
    name = models.CharField(_('name'), max_length=128)
    parent = models.ForeignKey('self')

# parent, assuming this person is spontaneously created
fred = Person(name='Fred')

# me and my brothers
zach = Person.objects.get_or_create(name='Zach', parent=fred)
trevor = Person.objects.get_or_create(name='Trevor', parent=fred)
austin = Person.objects.get_or_create(name='Austin', parent=fred)


zach.parent_set.all()
# [fred]
austin.parent_set.all()
# ...