Friendship is a major theme of the story princess September. 'The Friendship Between Princess And The Nightingale'.
The nightingale offers himself as a companion to the princess in place of her parrot, and the princess readily agrees. Friendship demands sacrifice. The princess loves the nightingale and shuts him in the cage so that she could have him all to herself. But, she soon realizes that the real happiness of the bird lies in its freedom. Thus, she sacrifices her own wishes and grants the bird freedom. It is difficult to place other's wishes before one's own. Only true friend can do this, and the princess September proves herself as true friend f the nightingale.
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