My neighbor has a great dane, and they are gone for the weekend so I went down to take care of him. I looked and my 18 week old female GSD had climbed the fence (my family let her outside assuming I was out there) Next thing I know she's barking at the great dane in a high pitched bark! Everywhere the great dane went she was running after him barking! Lol she would run after him barking then run back to me & stand beside me. I just though it was hilarious! The great dane was jumping in front of her, running, & playing with her while she was barking! Lol After this moment I have became curious though, when will she become protective?