Access index of the parent ng-repeat from child ng-repeat

My example code was correct and the issue was something else in my actual code. Still, I know it was difficult to find examples of this so I’m answering it in case someone else is looking.

<div ng-repeat="f in foos">
  <div>
    <div ng-repeat="b in foos.bars">
      <a ng-click="addSomething($parent.$index)">Add Something</a>
    </div>
  </div>
</div>