To express this, you would need to provide more context. For example, you could say:
* "Ke kaikamahine a ke kaikunane" (The daughter of the younger brother) if you are talking about the niece of a male sibling.
* "Ke kaikamahine a ke kaikuahine" (The daughter of the younger sister) if you are talking about the niece of a female sibling.
You could also use the person's name and relationship:
* "Ke kaikamahine o [name]" (The daughter of [name])
Remember that Hawaiian language often emphasizes the context and relationship rather than direct possession.