All About Asthma in Children What causes asthma? It may be partially inherited, but many other environmental, infectious, and chemical factors are involved. Your Child's Asthma How asthma will affect a child throughout his/her lifetime varies, depending on the child. Anatomy of the Respiratory System The respiratory system includes the nose, pharynx, larynx, trachea, and lungs. Asthma: First Doctor Visit for Your Child You may be wondering what questions the provider will ask or what tests and exams your child will need. Your Child's Asthma: How Severe Is It? Asthma levels are classified in "steps," because each child may step up or step down to different levels at any time.