To make you feel better I have a 5 year old boy that growls at everything. He has been like it since he was a puppy. At vets office they ask me to put the muzzle on because his growl doesn’t bother me. He is very friendly but as soon as you do something he doesn’t like he growls. I guess his way of letting you know his feelings. My other is a 7 year old girl and growls at nothing!!