Node Hierarchy: Display Children of top most parent in views Node Hierarchy lets you assign parent/child relationships to nodes, which can be displayed in Views. 

In Views, you can display the parent of a node, the ancestor of a node and the child of a node. (Instructions below*).

Is there are any way to combine this to display the immediate children of the top level parent node?

If not, are there any other modules that would allow this. (I have tried both relationship and entity references, but they don't seem capable).  





*Instructions on how to display Node Hierarchy relationships in Views. 

How to display Parent Node:
In Views, Go to relationships and enable the Node Hierarchy Parent relationship.
Then go to contextual filters, and selected Node ID as a filter. Under "When the filter value is available" set the Validator to content.
Create a block display and place it on your node.

How to display Ancestor Nodes: 
Exactly the same as Parent Node, but the Node Hierarchy Ancestor Relationship is used. 

How to display Child Nodes:
This requires a different approach from the above two, as a relationship is not used. The "Node Hierarchy: Parent Node ID" is used as a contextual filter in place of Node ID, however, the settings are the same.
You could try adding parent node as a relationship in views, then add a filter and set it to "is empty (NULL)" as a requirement of the field with relationship parent. This will only display nodes that have no parent node set.

If you want to show only nodes whose parents have no parent, you'd add a second relationship (called something like "grandparent") and then set your filter to require the grandparent, rather than the parent, to be empty.