All babies are born with blue eyes, and then the eye color of their changes. Why is this happening?

The answer is very simple! We just born children in the iris of the eye is no pigment, which is produced by the action of sunlight. Without it, most of the pigment eyes appear blue-gray to light and dark, if the light does not fall on the eyes. Over time, the child's eye color will become what should be on genetics. This is the development of children.