Hi Vicki,
I hope you register so that you can answer back our questions & suggestions. It's free & we really don't bite.... much :D
Is Zen neutered? If he's an intact male, he's reacting to situations by trying to dominate them & you. Even if he is neutered, this dog has a definite problem with accepting his place as the one not in charge. Remember, no matter how small & cute he is, he still is a dog, thinks like a dog, & reacts like a dog. He doesn't think he's human at all.... just that you are funny hairless looking dogs that can't talk :D
He is seeing himself in charge of 'protecting' you and the family. This is not good regardless of his size. I hope that no one thinks of it as cute and actually laughs at him. It doesn't help the situation. It could get himself killed one day by another dog or even a human who smacked him back.
There are several things you might try. Basically you have to let him know that
ONE you (humans) are in charge of all situations AND that
TWO his behavior is completely unacceptable.
First things first This is a daily exercise to let him get used to the idea that Zen is not in charge [$ needs to be more Zenlike. This is from AKC basic training to use as a first step prior to the beginning of training --- called Dominance-Down. It's worked on mine and other 'rescued' dogs to kind of relax them and acknowledge who is in charge. This will likely help for any dog to accept you as leader. If you're talking about dealing with other dogs, that's another tactic..this just deals with humans. No pain, no stress...well, not for long on the stress bit, at least ]-) It can help the dog to realize that you will take command in situations and it doesn't have to react.
Figure out about a half hour of free time on a daily basis. This is at first, as things start to get better, you can ease up to every other day..and so on. Don't schedule it around feedings or walks. You and your dog go into a room away from others. Be relaxed about it. Put tv or music on. Take a book/magazine with you. If you think you need his lead, use it, but make no issue out of it. Have him/her sit and then lie down.
Don't talk to her other than to give the stay command just one time. Then slowly rest yourself so that you are lying with his neck under your right or left arm. (with him being small, you might be over his shoulders & back, too.... Keep his head out. Might want to put him on a pillow & then drape yourself over him. Whatever you can do to become comfortable & your body is slightly lying over his, kind of as if he's an armrest. This has to be manageable for you to be here for about 15-20 minutes.. At least, that's your goal to work up to. He might lie quietly for 5 minutes and then decide to get up. Don't let him, but don't say anything. Just pull him back down by the underneath of his collar or where the leash is hooked in.
Your dog is there at your convenience, not his. He could go to sleep. Doubtful at first, but let him, if that's what he chooses. Use the time to read and relax. If s/he does struggle, make him do what you want until he physically relaxes. Then just give him about five minutes to let himself get used to the idea. Then sit up. Work up to the longer time.
Don't let this end on a negative and stressful fight. Thats why you work up to the longer time period. Make it positive for both of you--that's why you adjust her start time for this.
When you end this time alone with him, just sit up, but continue to ignore him. When you leave the room, don't say anything to your dog. Let him think about this new change of status for a bit. If you have any other problems with him not understanding that he is lower than the family members, have everyone do this on a regular basis. Just keep things as calm and low key as you can.
This has basically worked for everyone that I've known who has had problems with their dogs and placement in the pecking order-- all sizes, ages, and genders. (around 40+ in about 6 years since I've known of it).
There are several things that I like about this method.
1) low key & daily interaction -- helps to build a bond
2) Face is not near dog's mouth
3) Looming & making a dog uncomfortable is not used
4) No force or stress involved (anything that requires a battle of wills is trouble, in my book)
5) Results can be seen usually within first two weeks.
6) Freely given information & not trying to sell you a program :D
Second Zen learns that bad behavior is not acceptable.
Various ways ---
Anticipate that there WILL be a problem before it happens. Have him in another room when the doorbell rings & someone enters. When everyone is settled, then let him in. You might want to put a leash on him just so you can get a hold of him (do this before anyone comes over/rings bell/etc....) Have everyone ignore him, including you.
When he acts up, take the leash or pick him up carefully so as not to get bit --- eject dog out of room -- close door. When he becomes calm on the other side of the door, let him in. Don't say anything while you're doing this, other than a firm "No!".
Keep doing it. Give him about 10 times before he stays out permanently. & just enjoy the visit. Next day...ditto.
This is just one method. I'm getting really long now. I'm sure others will have wonderful suggestions too. Just think of it this way.... Your dog became a spoilt teenager [$ now he's a spoiled adult. Sorry, but it's the truth :( When he barks & carries on at the window....close the blinds, or put him out of the room.... I do it with mine & tell them "TV has been turned off" ]) Oooh, they react to that one quickly now :D
good luck
toodles