Niece and nephew

Child of one's sibling or half-sibling

In the lineal kinship system used in the English-speaking world, a niece or nephew is a child of an individual's sibling or sibling-in-law. A niece is female and a nephew is male, and they would call their parents' siblings aunt or uncle. The gender-neutral term nibling has been used in place of the common terms, primarily in specialist literature.

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