Ever since we got our second basenji, Stick, we've notice what we feel is displaced aggression with our older girl, Sophie. I walk my dogs on a split leash which normally works well from us. BUT if we see another dog being walked Sophie will immediately turn on Stick and attack him. Poor Stick always puts up with it and never fights back. I am now very aware of our surroundings and can usually see the other dogs before Sophie does. In which case I change directions so she can't see them. I've tried stopping and making her sit and focus on me while the dog is passing but it doesn't seem to work. A few weeks ago when I tried this method instead of attacking Stick she bit my boot because I was the closest thing to her. I want to stress that she never acts like this at any other time. It really is a Jekyll and Hyde situation. It's almost like she doesn't know who I am or where she is until the other dog is out of sight. Has this happened to anyone else? Any suggestions?