We just went into shedding 'season' here. Krypto is blowing his coat - what a mess, and even sleek Uhura's fur is everywhere. Dh got quite a bit of fur off both of them, as I think that it's smarter to groom outside, but there will be a lot more where that came from before this shedding is over.
We learned something odd about Hira...she doesn't have an undercoat. GSD's, except for some rare long-coated dogs, are always double coated. Weird!
I know the lunge you are talking about.
I have to control myself, not to trigger dogs to correct other dogs. My first instinct when a dog or cat is doing something wrong, is to tell them to stop it.
However, the natural way for a dog to act if their person is upset, irritated, or just being firm, is to look around and see the cause of the 'problem.' Then, deal with whoever they find in the area that they think is the root cause. In human terms, we might say that they are blaming the cat, dog, etc.
That can cause lunges, attacks, or fights.
The other thing that dogs can do, is decide that you may not want an animal in the vicinity, so they herd them out in some way.
We won't even get into territory or jealousy. Some people say that animals don't become jealous, that it's a human emotion that we incorrectly connect to them. I beg to differ.
Anyway, I find that I have to correct my own responses to things to keep everyone else's responses in check. Sometimes it's from many years, and that's a whole other issue.
Love All Life, Thank You For Posting! :)