Using Custom Fields to name Nav Menu

Hello,

I am trying to use the custom fields to name the menu in the template so when you create a new nav menu the names will match. My goal is to use the same page template for multiple posts instead of creating multiple page templates with different nav names that does not exist yet. Here’s what I’m using to call the nav menu. I would like to be able to change “Family Tree” I hope this makes sense because It’s hard to explain.

<?php wp_nav_menu( array(‘menu’ => ‘family tree’ )); ?>