Maybe you can try to keep them seperated. When the more dominant of the two enters a room the other must leave the room. Actually that could be part of the problem, maybe Chewy is confused about the pack order as far as things go with Teddy. Chewy might think he's more dominant but Teddy isn't getting that message or maybe he's getting mixed messages from you and your family about his place in the pekking order. I think calling a trainer is probably your best course of events though because they might be able to see hands on what is happening with Chewy and help you think of ways to correct the problem.