Profile: avansisI-2

function get_parent_page_for_api_bonos( $object ) {
  //get the id of the post object array
  $post_id = $object['id'];
  //return the post meta
  return toolset_get_related_post( $post_id, 'parent-cpt-child-cpt');
}
 
add_action( 'rest_api_init', 'create_api_posts_meta_field_bonos');
function create_api_posts_meta_field_bonos() {
  register_rest_field( 
    'child-cpt', 
    'parent_page', 
    array(
      'get_callback' => 'get_parent_page_for_api_bonos',
      'schema' => null,
    )
  );
}