Join Date: Dec 2012
Location: Silver Spring MD
German Shepherds are a really sensitive, intelligent breed. He understands that his sibling is different from the GSD in puppy class who is different from a "stranger" dog at the park. Unless he had exposure to dozens and dozens of different dogs before he hit 12 weeks (puppies, adults, seniors, large, small, hairy, not hairy, vocal, assertive, submissive, etc.), chances are his fear response is due to a lack of socialization and/or genetics. All that is left to do at this point is to desensitize through careful exposure to other dogs with LOTS of food, which will help to create a positive association for him. The process is sometimes slow, but it can be done, especially if you start now while he is still young.
I would get him out at least 2x per week for some sort of dog desensitization - group training class, working on your own at a distance from other dogs, or one-on-one play dates with other well socialized dogs. I would also leave your other dog at home for this training; otherwise, you scared dog will just rely on him for confidence and avoid the other dogs. It's also probably not a bad idea to hire a trainer with a lot of experience building confidence in dogs. And, I agree with spidermilk, no more dog park!
Iry, mixed breed, CGC
Max, GSD, CGC