My parents recently got a female 2 year old cairn terrier rescue called Sooty. She's a very loving dog and did well at doggy training but she is quite anxious and stressed, particularly when leaving the house to go on a walk. Whenever we get the leads ready she goes beserk, barking and attacking our other dog Pepper (an elderly 13 year old cairn). This continues for a couple of streets until she calms down. It's very difficult to take them out together on my own and is probably quite stressful for our other dog. She was rehomed as her previous owner had a stroke and could no longer care for her (completely understandable) so she doesn't have an abusive history. Has anyone had a similar experience or has any advice? Thanks!