Terriers are just natural born hunters. If they can get away with it, they will chase cats around the house. My Siamese and my dobe used to get along fine until i brought my russell, the 1st terrier. My cat can sense if they are hunters or not, he never trusted my russell. Now Nina comes in and terrorizes the whole situation. She even turned my Dobe against him and they all chase. But my cat just finds all the high places and has the whole downstairs for himself.
