public function getChildObject()
    {
        if (!$this->hasChildObject()) {
            return null;
        }
        $childObjectClass = $this->getDescendantClass();
        $childObject = PropelQuery::from($childObjectClass)->findPk($this->getPrimaryKey());

        return $childObject->hasChildObject() ? $childObject->getChildObject() : $childObject;
    }