My 3.5 month old GSD is scared when ever other dogs bark, near or far. If at my moms house he will run if her dogs bark at anything. Also while walking him, if he hears a dog bark in the distance or somewhere near by he gets scared and starts pulling towards home. Is this normal for a young pup? He has been socialized, met many other dogs/people/kids. Never to my knowledge had a bad experience with dogs barking.