Admin users can link related assets together by putting them into the Lightbox and then clicking on ‘link assets‘. This option creates a "peer" relationships between assets quickly and easily. If you are using multiple Asset Types or both peer and parent-child relationships in a single Asset Type, then this option will not be displayed. In that case, you can create and edit relationships at the bottom of the Asset Details page for any given asset.
All users will then see the thumbnails of the related items at the bottom of the Asset Details page when viewing any of the linked items.