Accessing parent's parent controllers through Angular require attribute

In the below example, the accordion-group directive shares a controller and scope with the parent accordion, using the "require: '^accordion'" attribute within the accordion-group directive.

If I wanted to create a child directive, under accordion-group, how would it access the accordion controller as well? Requiring ^accordion and ^accordionGroup do not seem to work.

https://github.com/angular-ui/bootstrap/blob/master/src/accordion/accordion.js

It does work that way. I was just being stupid. Fiddle for posterity here.

'use strict';

angular.module('myApp', []).controller('OneController', function() {
    this.test = function(element) {
        element.css('color', 'red');
    }
}).directive('one', function() {
    return {
        restrict: 'E',
        transclude: true,
        replace: true,
        controller: 'OneController', 
        template: '<span ng-transclude>And a </span>',
    }
}).directive('two', function() {
    return {
        restrict: 'E',
        transclude: true,
        replace: true,
        require: '^one',
        template: '<span ng-transclude>and a </span>',
    }
}).directive('three', function() {
    return {
        restrict: 'E',
        transclude: true,
        replace: true,
        require: '^one',
        template: '<span ng-transclude>and a one two</span>',
        link: function(scope, element, attrs, ctrl) {
            ctrl.test(element);
        }
    }
});