Check if a Page is a Child of Another Page in WordPress

This post has been updated in “is_child() Conditional Function for WordPress”.

WordPress has some default conditional tags that are really helpful when developing themes and plugins that need specific functions on specific pages. Strange enough though, there is no way to check if a page is a child of another page.

This small function checks the database to see if the page happens to have a parent page assigned to it. If so, then the function will return true.

function is_child($pageID) { 
	global $post; 
	if( is_page() && ($post->post_parent==$pageID) ) {
               return true;
	} else { 
               return false; 
	}
}

Place the above code in your theme’s functions.php file, or create a functions.php file and place it in your theme’s directory. Then you can use the is_child() function anywhere in your theme. Your code would look something like this:

<?php
if(is_child(343)) {
echo "This is a child page of 'The Parent Page Title'.";
}
?>