In a video uploaded to Facebook, Shelton‘s mother and Gwen Stefani serenade him as he’s about to blow out the candles on his birthday cake. “Happy birthday, dear Blakey,” they sing, much to his mother’s enjoyment. “We both said Blakey!”Stefani captured the sweet moment on video as his mother hugs hum around the neck and talks to the camera, saying hilariously: “I birthed this big thing!”