Child theme not visible in backend

Question

Assuming the parent theme properly enqueues it’s style.css, there is no need for your child them to also enqueue it. As follows:

parent themes’s functions.php

add_action ('wp_enqueue_scripts', 'parent_enqueue_scripts_styles') ;

function
parent_enqueue_scripts_styles ()
{
    wp_enqueue_style ('parent_style', get_template_directory_uri () . '/style.css') ;

    return ;
}

child themes’s functions.php

add_action ('wp_enqueue_scripts', 'child_enqueue_scripts_styles') ;

function
child_enqueue_scripts_styles ()
{
    wp_enqueue_style ('child_style', get_stylesheet_directory_uri () . '/style.css') ;

    return ;
}

and you’ll get an HTML <head> as follows:

<html>
    <head>
        ...
        <link rel="stylesheet" id='parent_style-css' href="https://wordpress.stackexchange.com/questions/260764/path_to_parent_theme/style.css" type="text/css" media="all">
        ...
        <link rel="stylesheet" id='child_style-css' href="path_to_child_theme/style.css" type="text/css" media="all">
        ...
    </head>
    ...
</html>