get_category howto

Im trying to show all child categories within a parent category on the single blog page. I don’t want the parent category link to display; just the sub categories. Im working in the template, content-single.php file so the categories are being output via:
the_category('');

According to the WP code reference we can use:
the_category( string $separator = '', string $parents = '', int $post_id = false )

$parents – to customise the output but neither of the 2 option:
‘multiple’ or ‘single’ allows to NOT show the parent category. Is this possible??