Well, I have to say that I originally saw cats too until you said they were supposed to be elephants. Now I DO see elephants, but I have a suggestion that may help. You can add an eye (with permanent marker) to some of the lighter colored elephants. It's the perspective that could throw it off, but putting the eye where it belongs definitely turns the observer's perspective to see the elephants. ...just a thought....
The quilt is lovely and your sister will love it for sure.