Subtask Alignment

Good day,

it would be great to be able to make a adjustments to dates between tasks (parent-subtasks or other dependent tasks) re-scheduling automatically. 

For example: A parent task has a number of subtasks. I would like to be able to give the parent task the option to reschedule both start and end date automatically, so that it starts when the first subtask starts and ends when the last subtask ends. Currently, sometimes it does adjust and sometimes not, and we have not found out why.