support for grouped data

Can't seem to find anything, so I think ELT does not support grouped data.

Lets assume countries and cities. one-2-many.

A row would look like either a country name or city name with some styling to give some visual clues. Action buttons would be needed on both (remove country or city).

Does ELT currently support such a scenario? I imagine I could create a row component that renders its own a partial table to display it's cities but feel that is not a correct approach.