Can a person's eye color (iris) change slightly with their mood?

wonderw
There are a couple of people that I know that it seems depending on their mood (happy, serious, angry) that their eye color changes ever so slightly.

I'm just wondering if anyone has noticed this phenomenon before?
Updates
+1 y
I'm wondering if it would make sense that if someone was excited...anything that caused an increase in blood flow/etc..more blood to the eyes, that might effect the color. Example, brown eyes turning a more coppery color.
Can a person's eye color (iris) change slightly with their mood?
2 Opinion