Cali Gorsuch just wanted to make a simple recording of herself singing. But Leo had other ideas. Yeah, you've heard dogs sing before, even dogs singing to music, but you've never heard this before.
Leo has impeccable timing. His pitch is not exactly perfect, but he carries a tune much better than I could. And he's got more soul in his voice than most human singers. You have to wonder how many times Leo has heard this music before. Even that wouldn't explain how good this performance is- he is just a talented little dog! And he looks just as cute whatever he's doing.