Every person, regardless of age, must have a passport to travel out of the country. Initial passport applications for children under sixteen (16) years of age must be made in person. Both parents of the child should be present. If one of the parents cannot be physically present, they may complete a parental consent form instead. This form must be notarized and a copy of the parent's ID must accompany the form. There are exceptions to the requirement of the consent of both parents including court order or proof of sole custody. Additionally, there is an application to obtain passport without the other parent on the basis of exigent circumstances and the unavailability of the other parent. You can visit the U.S. Department of State website for additional details on the requirements to obtain a passport at travel.state.gov.