We were up at the cottage this weekend with a few groups of family members all of whom came with dogs in tow. Unfortunately the first family didnt wait to let their dogs out of the car or leash them so their GSD Greta, and my little terrier Pete met in the doorway of our cottage, her hackles went right up and she kindof went for Pete. They were separated without any injury or real fight but for the rest of the weekend Pete would run and aggressively bark at Greta whenever she made sudden movements. It was totally out of character for such a usually calm dog, he even started doing it with the other large dogs after Greta left. I don't know if it was the one incident or a history that I don't know about but that behaviour really worries me. He's a little guy and all it takes is one dog who responds to the harassment so, what do I do? How do I desensitize him to big dogs and sudden movement in a way thats safe?