Besides through muttering, a baby will use the sound his crying to communicate with his parents. Parents do not need to hold the baby in arms whenever the baby cries; instead, respond to the crying properly and timely will enhance baby's feeling of safety and minimize the crying. The common reason for crying include feeling hungry or thirsty, having desire to pee or poop, getting tired; sometimes the room temperature, or baby's emotion (feeling bored or excessively excited), feeling pain or falling ill will cause baby to cry. It is even hard for an expert to tell what exactly the reason just by hearing the sound of baby's crying; however, parents can choose to try out things through reasoning (e.g. If there is a schedule to feed the baby some milk at 9:00am, but parents have not feed the baby till 9:15am, the crying should remind parents to feed baby on time). With a proper respond to baby's need, baby will soon cease crying.