def get_children_display(self, id, **kwargs):
Return a list of concepts or collections that should be displayed
under this concept or collection.

:param string language: Optional. If present, it should be a
    :term:`language-tag`. This language-tag is passed on to the
    underlying providers and used when selecting the label to display
    for each concept.
:param string sort: Optional. If present, it should either be `id`,
    `label` or `sortlabel`. The `sortlabel` option means the providers should
    take into account any `sortLabel` if present, if not it will
    fallback to a regular label to sort on.
:param string sort_order: Optional. What order to sort in: `asc` or
    `desc`. Defaults to `asc`

:param str id: A concept or collection id.
:returns: A :class:`lst` of concepts and collections. Each of these
    is a dict with the following keys:

    * id: id within the conceptscheme
    * uri: :term:`uri` of the concept or collection
    * type: concept or collection
    * label: A label to represent the concept or collection. It is \
        determined by looking at the `language` parameter, the default \
        language of the provider and finally falls back to `en`.