I have white hair which almost covers the right side of my head since I was about 5. It started out as a spot about the size of a quarter when I was 3. A dermotologist said it's called poliosis, which is basically a lack of pigment in my skin. It's also in my eyebrow, eyelashes and beard on my right side. I got a lot of shit for it when I was younger, now it's mostly compliments (although almost exclusively from old ladies).
I think you shouldn't dye it, and be thankful you have hair.