Band was joined by the legend and his two sons for a play through of “I’m Blue I’m Lonesome” at last night.

Earlier in the day the festival photographer snapped this shot…


So it was really no major surprise when we saw this one to follow it up soon after…

View this post on Instagram

Del and the boys sitting in with Trey.

A post shared by DelFest (@delfest) on

Check out the video clip below and stay on for the great Trey solo.

Band w/ "I'm Blue and I'm Lonesome Too" Delfest, Cumberland, MD 05.26.17