The letter should include the other person's contact details and details about the trip. It also helps if you've: evidence of your relationship with the child, for example a birth or adoption certificate. a divorce or marriage certificate, if you are a single parent but your family name is different from the child's.
It's important that you give your co-parent notice and preferably get their express permission in writing if you wish to travel outside the state with your child. If the other parent refuses to cooperate, you can ask for the court's permission in advance.