Instructions
Write details that relate to the pet. Add elements that are specific to the pet, such as a memory you have of the owner with the pet or characteristics that made the pet special. Usually what first comes to mind is the best memory to go with, as long as it will conjure up positive aspects of the pet.
Be as empathetic as possible. You may not have such a close relationship with your dog or cat, but maintain sensitivity toward the depth of relationship that this pet owner had. This was not simply an "animal" to this individual. If you do not have such a close relationship with your pet, or if you don't have pets, the best approach is to view this sympathy note the way you would view a sympathy note written for the loss of a beloved friend or human companion.
Try to relate to them, even if you really can't. This does not mean waxing poetic about how you felt when your pet died. The focus should still be on this particular pet and its owner. It does mean letting the person frankly know that you feel for what she is going through. After all, you must empathize in some way if you took the time to develop a caring note.
Keep it simple. Usually the most simple message, written after a personal anecdote or detail, is the best way to go. Sometimes lengthy emotional outpourings come off as less genuine as a few simple lines to express your caring.
Monitor how the person is handling his grief. Particularly if the person has lost a number of other companions, such as a close family member, the death of a pet can bring that person over the edge. Contact the person's church. Develop a support network. When you deliver the letter to the pet owner, invite members of the church to be there, too. That way the person will know he has support during this trying time. Again, treat it as you would the mourning process for a human--bring food and kind thoughts along with your card.
Personalize the note further with a memento. Frame a beloved photo you have of the pet owner and herr pet. If you can get access to it, take a beloved toy or collar and create a shadow box with such items. Give the pet owner a diary so she can write about her feelings, which will help her get through the grieving process. These accompanying items will live on long after the pet is gone.
How to Write a Sympathy Note for the Loss of Pet
Treat a sympathy note for the loss of a pet the same way you would treat a sympathy note for the loss of a human loved one. Pets are no different for many than their human family members. Write your sympathy note with sensitivity and empathy. Beyond that, the most personal, heartfelt messages are those that show the writer really knew the pet, and how much that particular pet meant to the pet owner.