I am so sorry for your loss. It is never easy to say goodbye to a beloved furry family member, and no matter how long they are with us, it is never long enough.
The only way you are going to be able to find out what killed Harry is to have your vet perform a necropsy. Did your vet say exactly WHY he thought that it might have been a case of poisoning? When Harry went for his walk was he with a family member and walking on a leash? If so, does the family member he was with recall anything of him picking up and eating something along the way? It just seems odd to me that the vet would single out poisoning as a cause of death without performing a necropsy.
Once again, I am so sorry for your loss.
Ghilly
My heart goes out to you and your family. So terrible to hear your loss.
Much love & sympathy. Pamela
I am so sorry for your loss and such a young dog. Unfortunately, unless you have a necropsy done, there just may be no way to find the answer.