public function fromUser ( $user_id ) {
		
	    $sites = $this->User->find('first', array(
	    		'conditions' => array(
	    			'User.id' => $user_id
	    			),
	    		'contain' => array(
	    			'Site',
	    		)
	    	));

		if (!empty( $sites['Site'] )) {
			return $sites['Site'];
		} else {
			return null;
		}
	}