Hi again..yes do try my suggestion and see how your yorkie reacts when someone else has him without you around. If he is good with other people and doesn't go to lunge or bite..then the problem lies with him protecting you..and he may need some training in that direction..to make him understand that no-one means you an y harm.
If on the other hand he reacts in the same manner with other people when you are not walking him etc. then maybe you should seek help from your Vet..firstly to make sure everything is well with him..and to ask their advice.
Something must have set him down this road...!!
Do let us know what happens..
