I've been paying attention more to that lately.
My hair color, for instance, I always thought was my mom's. It's a very distinctive brunette. I have natural blonde in my hair. It's very apparent after I've been in Florida or to the beach. During the winter it darkens. I've actually had to explain to my black friends and Asian friends that no, I don't dye my hair, it's just multicolored on its own. Anyway, I thought I inherited it from Mom until I saw a younger picture of her and realized her hair was much darker and basically dark brown without highlights. Then two of my cousins on Dad's side randomly inherited it. I asked my grandma and she said my grandfather's sisters had my color hair. My dad and grandfather had much darker.
So now when people say my mom and I have the same hair, I'm like, "Uh, no, that's not her natural color."