Due dates in your own Reminders

On iPhone the app can write every due date into a list in Apple's Reminders. Ticking one off there records the change here; the list is shareable with the rest of the household from Apple's own app, and Siri, the watch and the lock screen reach it without anything more from us. Our own notification stands down while this is on, so nobody is told twice. On every other platform the same dates export as a calendar file.