Usually eye color doesn't change for the whole life. But if you want to have some difference you can wear contacts in various colors. And there is a new kind of operation which can change your eye color permanently. However do remember that once you have the operation your eye color is unchangeable for the rest of your life. If you are ready to take it, you'd better take a completed checkout of your eyes and follow the doctor's advice.
As we all known, eye color can be decided by two distinct factors: the pigmentation of the eye's iris and the frequency-dependence of the scattering in the stroma of the iris. Eye color is thus an instance of structural color and varies depending on the lighting conditions, especially for lighter-colored eyes. The black of your eyes are permanent indeed unless you are old and you take some artificial ways to change it. That is, our eye color will fade with time flies. The only way to change your eye color permanent is take surgery. But you still can change your eye color by making up and wearing contact lenses.
It depends, for example if one parent has light eyes ( blue, green) and the other parent had dark eyes ( brown or black) the baby can charge his eye colour up to about 9 months to 1 year, same thing with hair colour. If the baby reaches 1 year of age with the colour he/she was born with it, it won't change after that.