How to display multiple nodes of a content type on a page displaying a parent node?
Just use a Views Attachment to attach another view After your first view.

Another similar option is the Entity Views Attachment module:


  "Eva" is short for "Entity Views Attachment;" it provides a Views display plugin that allows the output of a View to be attached to the content of any Drupal entity. The body of a node or comment, the profile of a user account, or the listing page for a Taxonomy term are all examples of entity content.
  
  The placement of the view in the entity's content can be reordered on the "Field Display" administration page for that entity, like other fields added using the Field UI module.


So the nice thing about the EVA module is that it allows you to easily place and manage the View from the Field UI of your content type. Thus, making the administration of this tacked on view a little bit easier for site administrators.