My basic idea is to find a kids toy with large, distinct buttons that can be pressed with a paw. I'll then gut that device and use the keys to interface with an Arduino. The Arduino will play back either a voice synthesized or prerecorded word that is associated with that button.
Words can be grouped to communicate simple ideas. eg. "Mom" "Food"
I hit the resale shops today and scored an input device bonanza!
So the Turtle is out and the new toys will have to be sorted through while I figure out an arrangement of buttons and segments that will work best for the project.