How to get related nodes before the deletion with rules

You can use following code in "Execute custom PHP code" for Actions of Rule.

  $master_nid = $node_id;              # Set current node id here.
  $field_name = $ref_node_field;      # Set reference node field here.

  // Load the 'master' node
  $master_node = node_load($master_nid);

  // Get the node reference items attached to this node
  $items = field_get_items('node', $node, $field_name);

  // Loop through and grab the nids
  $nids = array();
  foreach ($items as $item) {
    $nids[] = $item['nid'];
  }

  print("<pre> :: Reference NIDs");
  print_r($nids);
  print("</pre>");

Hope this helps you.

Thanks,
Snehal Brahmbhatt | AddWeb Solution
https://www.drupal.org/user/3147795/track

Duplicate of #893750: Event: "Content is going to be deleted"