You can enable hierarchical list in a related list?

A hierarchical list allows a related list to have the option to show child records associated with the parent. This can be useful to see all related records to a parent record in one view instead of having to drill into to each individual record.

Steps:

1. Go to a related list where you would like to enable hierarchical list

2. Right click on the column header to bring up the context menu and go to Configure -> List Control

3. In the List Control Form, find Hierarchical lists check box, check it and update the record

4. Now on the related list, you should see a black arrow that will allow you to see all child records