I want you to promise me Promise me that you'll be faithful Promise me you'll never be ungrateful Say the words that you will never be untrue And I'll sing a lullabye to you. Promise me that you will treat me kind Say the words that you'll always be mine Promise me that you will never be untrue, no And I'll sing a lullabye to you Sing a lullabye of loving Sing a lullabye when you are blue Sing a lullabye of happiness And I'll sing a lullabye to you Sing a lullabye of loving Sing a lullabye when you are blue Sing a lullabye of happiness Yes, I'll sing a lullabye to you.