public function removeChildById($id)
	{
		if(isset($this->id2index[$id]))
		{
			$tmp = $this->children[$this->id2index[$id]];
			if(isset($tmp->name))
				unset($this->name2index[$tmp->name]);
			unset($this->children[$this->id2index[$id]], $this->id2index[$id]);
			return $tmp;
		}
		return null;
	}