public function oneToOne($model, $childKey = null, $thisKey = null)
	{
		// Default the keys if not set
		$thisKey  = $thisKey  ?: $this->getPrimaryKey();
		$childKey = $childKey ?: strtolower($this->getModelName()) . '_id';

		return new OneToOne($this, $this->resolve($model), $thisKey, $childKey);
	}