all mine are chipped as well. I think that is just great that their dog is back home but does make me wonder if after 4 years you would get the same dog back ? They may have some tough times ahead but if it were mine I would be so happy to see him who cares ?
I hope they are able to handle it if the dog now does not care for them etc.
This kind of story makes me really mad though... I totally despise people who take a lost animal and don't check them for microchips... Four years is crazy...