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Eye color is very subjective (and dependent on skin/hair color) and patterns vary.

In rare cases, melanin (the brown) can be there and be overpowered by the blue, so while a person is genetically a "hazel," they appear to be a true blue.

Here is a heredity predictor based on a blue-eyed mom, an alleged blue-eyed dad, and a brown-eyed child --- the result being that the alleged father is "likely excluded" as the father. (You can play with the various iternations of this calculator.)

http://genetree.com/resource/CalculatorResults.php?T=2

If you would look on the web you would find out that there are at this time actually 3 genes responsible for eye color.

It is not as simple as you claim it to be.

http://www.seps.org/cvoracle/faq/eyecolor.html

Here's some more information:

http://www.thetech.org/genetics/ask.php?id=126

"It may be that hazel eyes are the result of genes different from gey and bey2. Something like hey for hazel. And maybe hey is a bit like bey2 and gey in that it comes in two forms—one that makes enough melanin for hazel eyes (H) and one that makes little or no melanin (b).

If this were true, the scheme for eye color would have to be changed. In the new scheme, you would have brown eyes if you had B, hazel eyes if you had H but not B, green eyes if you had G but not H or B and blue eyes if you only had b.

My gut tells me this probably isn’t the answer. Even though this sounds pretty complex, it seems like it wouldn’t be that much harder to tease out than green and brown eyes. So it is probably something else.

Another possibility is a variation on this theme. Maybe hazel eyes come from different versions of bey2 or gey. I said at the outset that there were two versions of each gene. But what if there were more? What if there were many versions that result in the various shades of color we see?

This is certainly plausible and some recent research suggests that this might be part of the story. But again, I’m just not sure. I would think the genetics again would be easy enough that it would have been figured out by now.

Another possibility is that there may be modifier genes. These are genes that would affect how much melanin bey2 or gey make. For example, you could get a gene that has gey make more melanin or bey2 make less. The end result would be hazel eyes.

What might this inheritance pattern look like? Pretty complicated.

Before launching into this, we need to remember one more thing. We have two copies of most of our genes—one from mom and one from dad. What this means is that there are actually a number of ways of combining genes to end up with various eye colors"