We have a SCWT, 7 year olds male. We love him, but unfortunately he is quite territorial and often aggressive. Not sure why, did we neglect training him well enough when he was a pup, or was the breeder abusive? Anyway, it's too late to fix it now, we just are careful with him and keep him away from strangers. We are considering getting another dog, but I am concerned about how they will coexist. Do any of you have any thoughts about breeds, sizes, gender, etc. of dogs most likely to do well with him? I would appreciate any opinions or expertise you might have. Thank you, Rick