I have a list view up top  with an item view down below based on  parent-child tables.   The parent being in the list view above, and the child being in the item view below.

When a user clicks a list row, I would like to update the child item display values  below without making a smart object call everytime a user clicks a new list row.  Within the children only one child can be marked as 'active' and I would like to display that in the item view.

What is the best way to approach this?