Dear …
I am very sorry to hear about the passing of your beloved little __(dog/cat/etc.)__. I know how hard this must be for __(you/you and your family)__. The unconditional love we share with our pets is more that words can describe. It is amazing how they work their way into our lives and deep into our hearts. These little angels become such a great source of joy and comfort to us and that’s what makes it so very difficult to say goodbye.
Please accept my most heartfelt sympathy for __(you/you and your family)__ as you grieve over this loss. __(Name of pet)__ was a wonderful little __(dog/cat/etc)__ and I know __(he/she)__ will be greatly missed. As an animal lover myself, I understand your sorrow and I’m here for you if you need me.
Sincerely,