/**
  * Fetch OmbMishandeling which references this OmbMishandelvorm. Will return null in case reference is invalid.
  * `omb_mishandelvorm`.`mishandeling` -> `omb_mishandeling`.`id`
  *
  * @param PDO $db a PDO Database instance
  * @param array $sort array of DSC instances
  * @return OmbMishandeling
  */
 public function fetchOmbMishandeling(PDO $db, $sort = null)
 {
     $filter = array(OmbMishandeling::FIELD_ID => $this->getMishandeling());
     $result = OmbMishandeling::findByFilter($db, $filter, true, $sort);
     return empty($result) ? null : $result[0];
 }