Moral of "The Dog and the Sow"?

I am assembling a book for my young niece and nephew. What do you believe is the moral or lesson for a child, or children in this case, in the tale of "The Dog and the Sow"?

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The Dog and the Sow

A Dog and a Sow were arguing and each claimed that its own young ones were finer than those of any other animal. "Well," said the Sow at last, "mine can see, at any rate, when they come into the world: but yours are born blind."

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Thank you so much for your help!