No. Of course it doesn't.
I have red hair and green eyes, my brother has blonde hair and blue eyes. My father was born in Norway, had blue eyes and blonde hair that turned dark as he got older. My mom came from German, English and or Welsh stock and was fair skinned and a redhead like me but had hazel eyes.
My brother married a woman who is part Irish, perhaps a bit Welsh and German but a quarter American Indian. She has very dark/black hair and dark brown eyes and what I would call an olive complexion.
Two of their children have similar looks, hair, eyes and complexion to their mother but their one daughters has blonde hair and blue eyes. And my SIL used to point that out to my mother who told her shed never have any blonde blue eyed children because it a recessive trait.
Of course just because some genetic traits are dominant, that doesnt mean they always push out recessive traits.
When we studied genetics, in school, it fascinated me and not only have I never forgotten it, but have used the theory to predict what my progeny and their's would look like, prior to birth. And yes, it works! But you have to know several generation's back, on both sides/parents, hair and eye color. :-)
What is the birth order position of your blonde niece?