Judy Woodruff:

It is hard to believe, but today marks three years since our dear friend and colleague Gwen Ifill passed away. We think of her all the time.

Her loss was especially felt by young journalists in the "PBS NewsHour" Student Reporting Labs.

Here are four graduates of that program who went on to be Gwen Ifill Fellows at their local PBS stations.

We asked them to write letters they wish they could have shared with Gwen.