Everything you need to write a declaration letter to the judge in your custody case: an example, a downloadable template, an outline and tips. Introduction to representing yourself in Pennsylvania.Each of the documents listed below inculde a blank form and the instructions to fill out that form. To write a parent custody letter, you should follow a formal structure and clearly express your intentions. Here's a general outline to help you get started. This article provides a comprehensive guide to writing a declaration letter for child custody cases, including a sample letter. This sample pleading is for informational purposes only. A Pennsylvania custody agreement is a contract between parents outlining rights and responsibilities regarding a shared dependent child. Fill in the top part of this form with your name and address and the defendant's name and address. You are the plaintiff.