Once, when you walked past a woman with an umbrella, and she reached down to stroke the dog, you saw his lip curl in a snarl. This alarmed you greatly, and so now whenever you see someone carrying an umbrella you tighten the leash, haul the dog towards you, and drag him away.
Indeed, things seem to be getting worse rather than better, and taking him for walks in the rain is impossible. A friend suggested putting an umbrella in the dog's bed so that he learns there's nothing to worry about, but this doesn't feel right to you. But this still leaves the question of how to handle his growing fear.
In addition, it's important to avoid actions that will make matters worse. This means never forcing the dog to face up to his fears, but counterintuitively it also means never soothing or petting the dog in a fearful situation.
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