I have never heard any of my cats sing. I have thoughts that they might: but it is more the mice that they try to catch which I think could sing. In ‘Josephine the Singer, or The Mouse Folk’, Kafka writes about such a mouse. Cats tend to fiddle, rather than sing.
You tell me, however, that your cat sings. This must be a very personal affair, which I applaud. To live with a singing cat and not to sell the story to a newspaper like the Daily Mail speaks very well of you. I would say that to have a singing cat and to keep it private suggests you are a person of integrity and, I would imagine, one whose life contains great things. If I were a cat that sang, or another creature with an unusual cast to my personality, I would look you up.