My Shih-Tzu/Lhasa-Apso turns on me

Question
Hi.  I rescued my baby, Dillon from a Pet Adoption center 2 years ago in St. Louis, MO.  When it was just him and me, they only behavioral problems I had were when he ate my things (I'm sure it was seperation anxiety because I worked at a psychiatric hospital a lot).  He's alittle over 5 now, and we've moved back to Springfield, MO where I'm currently living with my parents.  My mom and I began playfully slapping each other one night and he jumped in, we thought it was funny, so we played this game with him.  I absolutely love my dog, he's my son.  But his behavior has changed a lot.  At night if my parents go to bed before me, he'll go in there.  When I try to pick him up his eyes glaze over and he becomes this viscious animal and begins to growl and bite at me.  That's the main problem, which has been going on for a few months.  Then, tonight, I went to play with him while he had his bone in his mouth, and he turned on me.  My parens were saying "you can't let him get away with this", so I slapped his bottom, which he then tried to attack me.  I'm really hurt and horribly worried about him.  What does all this mean?  Thank you.

Answer
Oh my dogs do this all the time; with the bone, you can't teach them that thats not allowed (i've tried). Its theirs and they don't want anyone to take what they own. By slapping him, you told him that he had no rights to that bone and he was telling you that that bone was his. About the issue with him not letting you take him from your parents room, its happened with me, too. With my Border Collie, all I have to do is slowly walk her and stop every now and then to let her know shes okay. But with my American Bull Dog, I have to be firm and drag her out. With my two Pit Bulls, I have to be a bit nasty since their still intact and live outside, and then they'll move where I say. You could walk around with your arms crossed or something like that and not look at your dog when its done something you don't like and that shows your boss. When the dog acts up, you have to let them know, without touching them if its a problem, that you are boss and that they are not. Theres books on dog language and how dogs think and act, and even some sites you can have a profile of your dog on and join little groups and sometimes ask about the issues. I hope this helps and please feel free to follow up. =]