Just a few more links. Just for research to see if any of these things sound like your dog and to show you that so often dogs misbehaving and acting out is so frequently due to something going on with them physically. But not always - it could be some other stressors in his life associated with your lifestyle changes or schedule with him or another dog is giving him troubles and he's insecure. Whatever it is, you really need to find out even if you have to hire an in-home animal behaviorist after a thorough vet check, second opinion and all physical factors have ruled out. I sure hope you find a way to help your elder.
Sundown Syndrome in Dogs??? - Behavior & Training Forum http://www.yorkietalk.com/forums/sic...-syndrome.html The Pet Docs