
In the nine plus months that baby bakes away in mommy's oven, a lot of questions whiz through the heads of parents-to-be. One of those is often, what color will my baby's eyes be?
Baby inherits his or her eye color from you and your partner - one gene each.
The science website Athro.com explains it this way:
Individuals have an appearance (say brown eye color). Individuals also have genes. Each individual carries two copies of each of their genes, one from each parent. A gene often comes in two flavors (such as a gene for eye color that makes eyes brown or blue). An individual can thus have two copies of the gene with the same flavor (brown-brown), or two copies of different flavors (brown-blue). Human eye color is controlled by at least three genes, though we only understand two of them well.

Fair-skinned babies are often born with blue eyes. All children's eyes gradually change to hazel, brown, green, blue or gray eyes by the time they are three years old. Brown is the most common eye color. Gray is the least common, followed by true green.
For more info on the genetics of eye color, check out the Wikipedia eye color page.