Remove Parent Category from Child Category URL

Okay,
I found a solution which solved the category URL problem from child category URL’s
https://wordpress.stackexchange.com/questions/6106/remove-parent-category-from-permalink-basically-only-have-the-child-category

But it does not removed the parent category from posts URL’s.
ie:
https://mysite.com/parent/child/post-name
INTO
https://mysite.com/child/post-name

Anyone can help a bit further ?

Hii mianshahzadraza,
For Remove parent category name please add this code, this will help you.

add_filter( 'post_link', 'remove_parent_category', 10, 3 );
function remove_parent_category( $permalink, $post, $leavename )
{
    $cats = get_the_category( $post->ID );
    if ( $cats ) {
        usort( $cats, '_usort_terms_by_ID' );
        $category = $cats[0]->slug;
        if ( $parent = $cats[0]->parent ) {
            // Find parent categories and replace them in the link
            $parentcats = get_category_parents( $parent, false, '/', true );
            $permalink = str_replace( $parentcats, '', $permalink );
        }
    }
    return $permalink;
}