We have two cats, indoor only, male 6 months old and female 5 months, both recently neutered. I visited an animal shelter recently and am planning to bring home a small dog before it is euthanized (looks like about 2 years old) sort of a mix between a corgi and chihuahua in looks and size. We'll have to keep her inside because we don't have a fence and it will take a week or so to put an enclosure in. I'll exercise her on a leash until then. How do I introduce my two very indulged kitties to this dog, sho will now be sharing their 1,800 sq. foot kingdom (our home)? She looks scared to death in the shelter so I don't think she'll be aggressive.