How can I automatically add a taxonomy to my navigation?

So I have a navigation of custom taxonomies that I have added through Appearance > Menus

Navigation:

HOME | NISSAN | HONDA | TOYOTA | MORE

Now all of those are custom taxonomies of "Types" that I have made and manually added onto my menu. And those are all Drop Down Menus with sub categories to them.

Example:

I scroll over Nissan I see: - Ultima - Maxima

I scroll over Honda I see: - Accord - Civic

I scroll over Toyota and I see: - Camery - Corolla

Now all of that has been manually add though Appearance > Menus

But now my question is what if I add a new sub category to Honda that I want in the menu such as "Prelude"

How can the "Sub Types Taxonomy" Prelude automatically be added to the Honda drop down menu without me having to manually add it my self through Appearance > Menus.

Meaning I go to my "Types" taxonomy and I create a new Type named Prelude which is the child of Honda and I want that to show as I scroll over my Honda tab on my navigation. How can I achieve this automatically?

This is how my wp_nav_menu is added onto my header.php. (By the way I have used navwalker because I am using Bootstrap)

<div class="collapse navbar-collapse" id="consumers-liquor-navigation">
       <?php
            wp_nav_menu( array(
                'menu'              => 'primary',
                'theme_location'    => 'primary',
                'depth'             => 2,
                'container'         => '',
                'container_class'   => 'collapse navbar-collapse',
                'container_id'      => 'consumers-liquor-navigation',
                'menu_class'        => 'nav navbar-nav',
                'fallback_cb'       => 'wp_bootstrap_navwalker::fallback',
                'walker'            => new wp_bootstrap_navwalker())
            );
        ?>
    </div><!-- /.navbar-collapse -->