I created template where one of the rems has 2 descendants. When I want to add that slot, it just adds parent rem, but not 2 descendants.
Perhaps I should add that both, parent and children rems, are designated as “slot” within my template.
Always helps to post a screenshot - or even better your rems for copy&paste - to let people figure out what went wrong in your case 
I have the same question, maybe someone can dig into this if I provide supplementary info.
I created a document where I put my templates. It is inside a portal and looks like this:
When I test it, inside the same document (where I put my templates), the concept and all the descendants are shown.
However, when I use the template in another document, I encounter the same problem like Mechkalito. There is always a descendant missing. I spent 2 hours, deleting and retrying but everytime I get this really annoying problem.
Hope this helps somebody to find a solution. The solution cannot be that portals only work inside the same single document.
Here’s and example (notice that children of level 3 are not recreated in Rem that uses it as a template)
If I add tag that automatically adds all slots, this problem disappears. It appears that issue it with manual approach. Hope developers see this bug.
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