public function getRelation($respondentId, $relationId)
    {
        $filter = array(
            'grr_id_respondent' => $respondentId,        // Just a safeguard to make sure we get only relations for this patient
            'grr_id'            => $relationId
        );

        $data = $this->loadFirst($filter);

        if (!$data) {
            $data = array();
        }

        $relationObject = $this->loader->getInstance('Model_RespondentRelationInstance', $this, $data);

        return $relationObject;
    }