Why Your Dog Growls At Some People And Not Others

Mistreatment: The specific person may have mistreated the dog or someone who looks, sounds or acts similarly to someone who mistreated them in the past. Your dog may show their teeth, pull their lips back, stiffen their tail, or simply try to avoid the person.

Excitement: The person is someone your dog knows well or has had contact with in the past, and they get excited when they see them. Your dog may show their excitement by wagging its tail and excessive licking.