See what documents a child needs to travel to or from the US alone or with a parent or relative. Non-US citizen children traveling to the US.The intention of this letter is to provide consent for a minor child to travel without the company of both legal parents. It's just a freeform letter that says your children have permission to travel with their other parent. A Child Travel Consent Form is required where a minor child under the age of 18 is traveling internationally without both parents present. Please fill out one of the form choices and the Consent to Treat Minor Children Form. Here are the steps to write one: 1. Document Header - Begin with a clear and descriptive title, like "Child Travel Consent Form." We will be sharing some family travel tips about what documentation is needed, such as a travel consent letter, for international travel with a minor. There is no standardissue minor travel consent form.