I have blond hair
Well are you male or female? Because males have blond hair and females have blonde hair!
I guess I have blonde hair then. I am a female. I always wondered why there were two spellings.
I didn't have know that until recently either! Blond hair is based on having low levels of dark pigment called eumelanin!
So is it some sort of a defect?
Blond
Blond or fair hair is a hair color characterized by low levels of the dark pigment eumelanin. The resultant visible hue depends on various factors, but always has some yellowish color. The color can be from the very pale blond (caused by a patchy, scarce distribution of pigment) to reddish "strawberry" blond or golden-brownish ("sandy") blond colors (the latter with more eumelanin). Because hair color tends to darken with age, natural blond hair is generally rare in adulthood. Naturally
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There is also a variety of hair colors. The African-American dolls have black hair; Hispanics have brown hair, and the others had blond, ash-blond/two tone, brunette, red, and (in the last year of production) strawberry-blonde. 
Hair styles varied as well. African-American girls all came with "curly pigtails" (two pigtails with a short fringe right around the head). Hispanic girls came with a v-part style (little bunches on either