rynokins

<?php
// Loads FontAwesome & assigns dashicon prefixed classes to correspond to FontAwesome 5 (free) fallbacks. 
// This allows 'dashicons-' to be used when declaring custom post type icons.
// Added padding-top tweak to align better
// Pick your icon here: https://fontawesome.com/icons (make sure to search 'Free' icons)
function font_awesome_icons(){
	echo '<link href="//use.fontawesome.com/releases/v5.5.0/css/all.css"  rel="stylesheet"> 
	<style> 
		.dashicons-before:before { font-family: dashicons, "Font Awesome 5 Free"; }
		.dashicons-calendar-plus:before { padding-top:4px !important; content: "\f271"; } 

rynokins

function if_page_or_ancestor_page_is($page_slug = NULL)
{
    $is_page = false;
    if (is_page()) {
        global $post;
        /* Get an array of Ancestors and Parents if they exist */
        $parents = get_post_ancestors($post->ID);

        $all_pages = array_reverse(array_merge($parents, array($post->ID)));