protected function declareOneToOneRelationship(
        $sourceModelName,
        $targetModelName,
        $sourceColumnName,
        $targetColumnName,
        $navigationPropertyName = ""
    ) {

        $oneToOne = new OneToOne(
            $navigationPropertyName,
            $sourceModelName,
            $sourceColumnName,
            $targetModelName,
            $targetColumnName
        );

        $navigationPropertyName = ($navigationPropertyName) ? $navigationPropertyName : $targetModelName;

        $this->addRelationship(
            $sourceModelName,
            $navigationPropertyName,
            $oneToOne
        );

        return $oneToOne;
    }