What power does Nanny Flowers have over Koro? And what power does Koro have over Nanny Flowers?

Nanny Flowers is a strong personality. She is willing to think outside the box and point out the facts to her husband, even when he doesn't like them. Nanny is brave and indepenent, thus, she is able to speak her mind and urge her husband to do what is right..... not what is expected.

Koro is the leader of the Maori people in a patriarchal society. In the end, it is Koro who will make the final decisions. Koro's is a strong leader, he is also obstinate. It is his wife's innate strength of personality that allows her to stand up to him.