#7 Chihuahuas are great dogs, but they can also be very stubborn. If there is no consistency in their upbringing, they will take advantage of it at every opportunity. And what initially seems cute, then becomes an everyday problem.
#8 Especially when meeting other dogs, owners should attach importance to friendly contacts.
Under no circumstances should barking, growling, and attacks be tolerated. Even if these are supposedly cute - for the Chihuahua they are an expression of fear and stress. If owners let this behavior go, the dog feels vindicated and will gradually see every strange four-legged friend as a threat that needs to be driven away.