Northfield Mountain Lion

Sunday September 6, 2015 at about 10:00 am, three of us saw a german-shepherd-size mountain lion casually walk through our back yard. He/she looked exactly like the one shown on this website. We thought it was a bobcat, but were told that the long tail indicates that it was probably a mountain lion.
We have only 1 1/2 acres on a corner lot with neighbors on each side, woods nearby. The mountain lion walked along the back property line, disappearing into the brush between our house and our neighbors.
Though he was a gorgeous animal, I wouldn't like to see him again in the neighborhood; I worry about my small dog and young grandchildren playing in the yard.