public function _relate($rels = false)
	{
		if ($rels === false)
		{
			return $this->_data_relations;
		}
		elseif (is_array($rels))
		{
			if ($this->_frozen)
			{
				throw new FrozenObject('No changes allowed.');
			}
			$this->_data_relations = $rels;
		}
		else
		{
			throw new \FuelException('Invalid input for _relate(), should be an array.');
		}
	}