/**
  * Get last notification of the given
  * entity, second parameter can filter by
  * category
  *
  * @param         $to_id
  * @param null    $category
  * @param Closure $filterScope
  * @return mixed
  */
 public function getLastNotification($to_id, $category = null, Closure $filterScope = null)
 {
     $notification = $this->notification->entity($this->entity);
     if (is_null($category)) {
         return $notification->getLastNotification($to_id, $filterScope);
     }
     return $notification->getLastNotificationByCategory($category, $to_id, $filterScope);
 }