What would be the reason that someone’s eye color would change from blue to green when they were a child?

Your eyes don’t change color, they only reflect the colours around them in particular if they are light coloured eyes. My eyes are blue-grey with a green heterachromia. They are very sensitive to light and dust so they get red easily which makes the eye color appear a brighter blue. If I wear green, the appear more green in color, when I am sunburned they appear more turquoise, etc. But when I wear white or don’t have a shirt on, they look their true blue-grey.

Where is the chart?

2hydrogen and 1 covalent