Edith Lank's Adventures in the Land of Aging
I propose that you may have a new subspecies of gray squirrel. Let's tentatively dub it Sciurus carolinensis lankensis. I'm hoping that it adopted the red streak in honor of the red-haired Lank family members.
http://resources.waza.org/files/images/w(415)h(252)c(1)q(90)/363cfa1873573e20a45d25f3603a836d.jpgAmerican Red Squirrel. Note the eyering. Pretty weird, though, if you have never seen one before in the past 50 years? Maybe it is a hybrid? But I can't find anything on line suggesting that they do.