I may not be of any help at all, because I have three doggies and they all get along fine. even when my yorkie had puppies she didn't mind the other two at all but i separated them anways.
the only time there was ever any slight bit of jealousy is when im brushing one dogs hair, they all want their hair brushed at the same time
in due time, i'm planning to get another yorkie, to make 4 be the complete total of my household
