FCCS Final Child task does not trigger task complete email notification

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We have several parent tasks with multiple child tasks underneath. Each of the child task has viewers assigned so they are notified via email of completion. However, I have noticed that the final child task does not trigger a task complete email notification to the viewers, as the other child tasks did upon completion. All child tasks are setup with the same viewer Team.  

When the final child task is completed, the task completion email is never sent to the viewers. It just autocompletes the parent task & send a notification that the parent task is complete. Is this intentional? Or is there a setting we can change so that every child task triggers the task complete email even if it is the last child task in a parent task.