query GuidelineNavigationItemChildrenChildren {
  guidelineNavigationItem(id: "…") {
    ... on GuidelineDocumentGroupNavigationItem {
      children(limit: 25, page: 1) {
        items {
          ... on GuidelineDocumentNavigationItem {
            children(limit: 25, page: 1) {
              items {
                ... on GuidelineDocumentPageNavigationItem {
                  __typename
                  id
                  isHiddenInNavigation
                  isPublished
                  title
                  url
                }
              }
            }
          }
        }
      }
    }
  }
}