Unfortunately, just like any dog, your small dog could become that way if he is not properly trained, but your Havanese puppy could also grow up to be a loyal, obedient, and affectionate companion. Your puppy might even become a Service Dog, Therapy Dog, Canine Good Citizen, Emotional Support Animal, or simply a well trained best friend, who is portable enough and well trained enough to accompany you everywhere that dogs are allowed.
Your Havanese puppy can benefit a lot from training. Not only will he or she be more pleasant to live with, easier to take places, and friendlier towards others, but your puppy will also be happier when he is given the attention, mental and physical stimulation, and purpose that training provides. 'Sit' is a wonderful command to teach, especially if you are just getting started. Not only will it make other commands such as 'down', 'heel', and 'stand' easier to teach, but it is also a great command to practice around your home, to teach your puppy to pay attention to you, respect you, trust you, and learn better self-control.
If your puppy is very young or timid, choose a less intimidating method, such as the 'Lure' method, for teaching 'sit'. If you are having trouble getting your puppy to sit when you do not have a treat in your hand after he understands the command, the 'Position' method might help.
Do not use the 'Position' method if your puppy has ever shown any form of aggression or is afraid of being touched. If your puppy is showing signs of aggression at this or any age, do not wait to seek help from a dog trainer in your area. The earlier that aggression is treated, the better the chances for a positive outcome. Aggression in a young puppy is serious.
If you choose to use the 'Position' method, then do not force your puppy's bottom to the ground. You are simply applying pressure to the base of your puppy's tail to encourage your puppy to lower his bottom to the floor on his own, in order to escape the uncomfortable sensation of your fingers. When you lift up your puppy's chin, do so gently. If your puppy squirms away from your hands, then simply try again, being gentle and patient, until your puppy sits.