'Supervise somebody doing something.'── quoted from Oxford Learner's Dictionaries.
Having read the above, I think it is correct to say 'to supervise his son ruling the kingdom after his death'.
Interested in Language
Is the following usage of the word "supervise" correct? If not can you tell me how to use it in the following context:
"The king was old and had one son, who was only ten years old. So the king appointed a guardianship council to supervise his son, after he dies, in ruling the kingdom."
I'd say "... after he died".
When I saw '... after he dies', I thought the king was still alive.
I am not a teacher.
If we used '…after his death' it would make no difference whether the king's still alive or not.
I am not a teacher