When I remove parent items from other grids so that they are only assigned to one date field (e.g. Appointments), I usually only come across them in the calendar. However, there is no indication in the calendar that these items have children. I can use the properties pane to check for existing children, of course, but I'd find a visual clue in the calendar (to remind me that there is additional info in the form of children attached to these items) quite useful. (Similar to the one now used for recurring events).

 

Of couse, it would be even greater to somehow be able to view these children directly through the calendar interface...

 

Cheers!