>from a biological veiw, you have as much DNA in common with your neices and nephews and you do with your grandchildren. In kinship terms, they are equal relations.


Which doesn't even come close to addressing the difficulties caused by using the same word for all three. Remember, this is a language that distinguishes between male and female cousins, cugino and cugina, yet does not distinguish at all between a nephew, a niece and a grandchild. And remember, this a question about words, not about biology.


noho ora mai
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