I'm not a dog trainer, but I'm wondering if the mother might be instigating it? I say that because of the "different bark," and I know exactly what you mean. I have four, and I know each dog's "voice." I can also tell the difference between "I see a squirrel on the deck" bark and a bark that says something is wrong and I need to run into the room to see what's going on.
Some on here will probably have better suggestions, but I'd suggest you look into a socialization class where you can take both of them and work with them together. Sometimes even the local Humane Society or pet stores do those.
As far as barking at strangers when they're walking, that depends on what kind of bark. Dogs sometimes bark a little just to say hello. If they're doing "the" bark, that could mean they're trying to ward people away from you or themselves. All the terrier breeds are very territorial. When mine bark at people (only two do it), I crouch down by them and hold their chins up to make them look at me, and tell them "quiet." That works for me, most of the time. |