What am I to my niece's daughter?

Her great-aunt or great-uncle (grandaunt/granduncle).

What is my niece's daughter to my daughter?

Your daughter's first cousin once removed.

Your niece's daughter is your great-niece (also called grandniece or grand-niece); you are her great-aunt or great-uncle.

Your niece's daughter is your great-niece (also called grandniece or grand-niece); you are her great-aunt or great-uncle.

12.5% shared DNA on average. Real amounts vary.

you them common ancestors double line: marriage

Your niece's daughter is your great-niece, also called your grandniece. Your niece's son is your great-nephew (grandnephew).

“Great-niece” is the everyday word. Genealogists prefer “grandniece”, because she's in your grandchildren's generation. Both are correct.

How we worked it out

Follow the chain one step at a time:

Your parents are her great-grandparents: they are your common ancestors.

She is 2 generations below you.

…

Tap relatives in order, like mother, cousin, daughter

More: grandchildren, great-, half-, step- and in-laws

Any sex Grandchildren and great- Half Step In-laws

Or type it the way you'd say it

…is what to

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