Emmie was almost 3 when we got our new baby Yorkie and she still hates her!!! I guess I could say she is a little more tolerable of her but not much. She is very, very jealous. She had never been around other dogs much and when she was (except for our big outside dogs) she did not like those dogs either. We thought she was lonely here at the house all day while I worked at the computer, wrong.......I was going to put a post on here about anyone knowing if there was a way to help them to get along!!! Izzy B. is now 4 months old but still all puppy and wants to play so badly but Emmie will have nothing of it, growls and snaps at her all the time. I have tried supervised play time but that doesn't even work so mostly I just keep them separated.
Good luck!!!!