No matter how rugged your night was, no matter how little sleep you got, how late you got to bed, how many times you were up, or how early your wake up call, sing this song, and I guarantee you will feel better. I know you don't feel like singing it, I know you're tired and crabby. But do it anyway. It'll help. I promise.
(It also helps if you have the encouragement of a six-week-old's grins and a five-year-old's giggles.)