This (rescue) dog was 10 years old when we got her. The story (you never get the full story from the rescue because they don't usually get the full story) was that she belonged to an old lady for, for some reason, could no longer care for her. The lady's daughter took Dog and tried to keep her but just wasn't up to it, so Dog was surrendered to the rescue. She was fostered for about three months before we adopted her. Dog was never the sharpest tool in the shed, but it struck us as odd that she had no idea what to do with a dog toy and she was so poorly socialized with other dogs. Based on pretty much every other dog I've known, play was innate. Even if the dog was not a genius, it could figure out a squeaky toy.