Show ancestor of a Custom Post Type

Hi guys ??
Well, the thing is, i have a custom post type named DISCOGRAFIA wich is a parent of MUSICA.
Well, in single-musica.php i have the content shown up, but i need to get the thumbnail and some custom fields from its parent on DISCOGRAFIA
eq: post type musica ID 222 is child of discografia id 20.
When showing musica 222 content, i want to retrieve discografia 20’s thumbnail.

I tried ′`$parents = get_ancestors($post->ID, ‘musica’);
echo $parents;
print_r($parents);`′
it prints an empty array

i tried
′`echo $post->post_parent;
$argss = array(
‘p’ => $post->post_parent
);
$parent = new WP_Query( $argss );

while( $parent->have_posts() ) : $parent->the_post();
echo $post->ID;

echo get_the_post_thumbnail( $post->ID, array(100,100) );
endwhile;`′
all empty again…

well, im using “types plugin” to manage custom post types and fields. it has some documentation with custom functions, but none for what i want.

=) hope someone can help me