behavior of a rescued dog

Question
Dr. Conner,

My wife came across a Chihuahua from a woman who has several of her own. She is not a breeder, just loves Chihuahuas as she says. I call it a "rescued" dog because of the following circumstances: the Chihuahua is just over one year old. This woman sold the dog to a couple who took it home and within an hour it escaped from their property. They and the woman posted flyers for it and after a week they received a call. It had been captured and contained in a massage parlor by the people that work there. Upon retrieving the dog, and within 3 days, the woman (the original owner) met my wife and interviewed her. We were told of it's ordeal and that he was very nervous and frightened. The Chihuahua has been in our home for the past six weeks. We have not paid for it, with the woman wanting to ensure it will adapt to our home first. Here is the problem:

Since coming into our home my wife had showed it nothing but love and is the one who feeds and holds him. This Chihuahua acts as if it is very afraid of my wife - running from her, cowering in corners or behind furniture, growling when she goes to pick it up, and once has bitten her. Times she catches him and holds him, petting/stroking him for hours, does not seem to make a difference. My wife has more patience than I do. She is heartbroken over it's behavior and I told her to give it back (which the woman has agreed to), but she insists on trying to convert him into loving her back. She has never swatted him, or anything like that, either. The dog is indifferent towards me, sometimes running away and other times allowing me to walk over to it as it reclines on the couch and petting it. Our 17 year old son, who really never pays it any attention during the day, is another story. The dog follows him around, plays with him and sleeps in his bed. My wife has brought him into our bed a few times, but he usually just freezes up (unknown if he actually sleeps through the night). For whatever reason this dog appears to be terrified of my wife, who shows it nothing but love.

Any suggestions on how to get over this hump? We are dumbfounded. Thank you for your anticipated response.

Answer
The fact that the dog has bonded to your son, who is giving very very strong "dog signals" of high rank, is GOOD.  This means the dog's bighting is the product of confusion and fear.  You and your wife must approach this animal in the same way as your son.  Do not overload him with physical attention.  Do not force him to sit with you.  Do NOT OFFER FREE AFFECTION OF ANY KIND.  Begin to ignore him.  Observe how your son treats him and follow that method.  It might take the dog a while (several weeks) to begin to see you in a new "light", but it will happen.  When he seems calmer around you, begins to follow you, etc., then begin handfeeding him one of his meals every day.  You should have rehabilitated this developing problem within a month.  Please repost with further updates.