So some background may help the Child's Play folks address my question.
We had a cat, Denver the Wondercat. One of my first posts on my old blog featured our 17-year-old feline with chronic kidney disease.
He did not like the "kidney diet." He did not like the pills. He especially disliked the pill holders. Fish flavored? Guess not.
Then we started giving him fluid infusions. Three nights a week my husband would hold him while I inserted a 14 gauge needle into the loose skin on his back and let 250 mL (~8 oz) of saline with potassium run in.
Median survival at the time of his diagnosis: 6 months. Denver made it almost 2 years. They were high-maintenance years, but well worth the effort.
I started telling patients about my cat with kidney disease. The diet, the pills, and the shots were far more interesting when I explained how they helped my cat than when I explained how they helped my patients.
Then I flipped through the Disney DVDs we own, and I realized that talking animals dominated the genre. The Disney people are not stupid; they know how to get to kids!
Anyway, I have been working on a book about Denver (I'm still looking for an agent) that I hope will help children with kidney disease and their siblings better understand their treatments. Children and grandchildren of adults with kidney disease may also enjoy such a book, and kidney disease is the most common cause of death in pet cats in the US.
But I still wonder why children identify so strongly with my cat or other animals, animated or living. I'm waiting, Child's Play.