How to Help Your Child Cope With the Death of a Pet – eHow.com
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“Memorialize your pet in a way that is unique to your family. Plant a tree in your pet’s favourite spot in the garden, write down thoughts about fun times spent with the pet, draw pictures, or hang a favourite photo of the pet in your home for all of the family to share.

STEP 8:
Show your own grief. Children will grow to understand their own feelings better if they see that their sadness is shared by other family members.”

These are good suggestions for art/journaling therapy.