Deletion in Realm seems to be incredibly underdocumented ... or am I missing something? How do you delete objects from Lists? Where are the examples?

I have object A with a List.
I have another object B also with a List
C has a reference back up to its parent A

I want to delete a B and all its sub-objects C. If I delete a C I want to remove it from its parent collection A as well.

I am stumped ... and find it unbelievable that Realm docs provide only two examples:

```
try! realm.write {
  realm.delete(cheeseBook)
}
try! realm.write {
  realm.deleteAll()
}

```