@Override
  public PresentableNodeDescriptor getChildToHighlightAt(int index) {
    final Collection<? extends AbstractTreeNode<?>> kids = getChildren();
    int i = 0;
    for (final AbstractTreeNode<?> kid : kids) {
      if (i == index) return kid;
      i++;
    }

    return null;
  }
@Override
  public PresentableNodeDescriptor getChildToHighlightAt(int index)