I totally agree about the link between stress and graying hair. I'm not sure about it being reversed when stress eases, though. I assume my past stress played some part in kicking off my gradual graying. In my case, I didn't see a rapid change, though. I'm 50 and have been having my hair colored for at least 10 years now. Before that I'd just pluck out stray ones. My mom went gray in her 20s. I'm sure there was a genetic element in her case.