A quiet suburban neighborhood was shaken this week after home security footage captured a tense standoff between a family dog and a mountain lion that wandered into a fenced backyard just after midnight. The black-and-white night-vision video shows the family’s German Shepherd stepping onto the stone walkway after hearing movement near the fence line. Moments later, a mountain lion appears from the shadows, approaching the yard before the two animals meet face-to-face. The Shepherd immediately b