public function getChildrenCount($categoryId)
    {
        $select = $this->getConnection()->select()->from(
            $this->getEntityTable(),
            'children_count'
        )->where(
            'entity_id = :entity_id'
        );
        $bind = ['entity_id' => $categoryId];

        return $this->getConnection()->fetchOne($select, $bind);
    }