Recently, I received a very nice email from Karen L. Allanach who is the Associate Director for Animals & Religion at The Humane Society United States.  Karen was nice enough to inform me about a few resources they have created on their website, which might be of help to you and your family. Specifically, you may want to check out the following:

St. Francis of Assisi:  Patron Saint of Animals and Ecology

An overview of the Roman Catholic Church's teachings on animals and animal protection

Additional Animals & Religion related resources from a variety of religious perspectives