Editing on one layer only shows when toggling a different layer

Ok, I m not sure exactly how to explain this....

Screenshot: I am working on "Sheep 3" layer...using the brushes and eraser to create my image, but no changes are seen on this actual highlighted layer, unless I toggle on OR off the visibility of the the layer BELOW it....

Notice in the next screenshot, the layer below the highlighted layer is made visiable and THEN the edit on the highlighted layer shows. 

This is in the newest update. Here is my system info:

HELP!!!!