Know what documents a child needs to travel to or from the U.S. All children, including infants, must have their own travel documents. Airlines typically require parents or guardians to fill out an Unaccompanied Minor form detailing flight info and emergency contacts.A child travel consent form is strongly recommended if a child travels alone, with only one parent or an authorized adult. Some parents are able to travel absent notarized letters if their order of custody gives them passport authority. They should carry a notarized letter from the absent parent or parents authorizing travel into Mexico. The DS3053 form is for situations where only one parent or guardian is able to fill out the paperwork.