I don't have any knowledge of what could have happened to your dog, but would like to say I'm sorry to hear of her death. My dog
is also twelve, and at the vet
last week I read on a chart that she is beyond being a senior, she is in the geriatric stage, which yours would have been too. Its hard to believe their that old, you can at the very least be comforted that she didn't have a disease that you would have to watch her suffer with, or have to euthanize her.