Hi,
You may display the children of appropriate documents by configuration of Path (in listing and viewers web parts). Here is more information about path formats:
http://devnet.kentico.com/docs/devguide/appendix_b___path_expressions.htmOptionally, you may use the Maximum nesting level property to restrict the documents only for one or more levels.
Regards the link to parent: you can e.g. insert the link on the parent document (e.g. Static text or Editable text web parts) and display it only for particular document types or add the Visibility condition not to display it on the parent daocument. If children uses the same template it will point to the parent.
The Web part documentation is here:
http://devnet.kentico.com/downloads/KenticoCMS_WebParts.pdfBest regards,
Helena Grulichova