It gives us integrity. It gives us happiness. Yes - a baby is sinless in the way that the baby has never lied. The baby has never stolen a penny. But each person is born with what theologians call original sin.
Original sin means that the child is born genetically selfish.
Jesus told us that we must be born again. This means that something has to come inside of us to make us realize that we must die to the selfishness that is a part of our original, sinful nature. We have to be born again. We must be motivated to become beautiful people to those around us. We must turn off all the negative faucets in our culture and in our world, that are flooding us with selfish, ego-centered thoughts.