Hi, mrsreeder. The child theme’s functions.php file is loaded before and in addition to the parent’s functions.php. That means that you only need to put open/close PHP tags and your new code in it. Please see this Codex article for a detailed description: http://codex.wordpress.org/Child_Themes#Using_functions.php
One more thing, mrsreeder. It’s worth noting that you’ll need to make sure that Jessica’s snippet lives only in one or the other functions.php file, not both. Defining a function of the same name twice would definitely gum up the works.
Hi, mrsreeder. As itβs been over two weeks since your last reply, Iβm going to close this thread. Please open a new one if you choose to pursue this further in the future.