So, Prince Francis is not only, like, ten years older than he should be, but he is also quite capable. He makes swords. And he has a good philosophy to go with it: Even kings should have a trade. In case their kingdom falls and they have to fend for themselves.
(Because this is France in the 16th century, hence they don't know yet what happens to kings when their kingdom falls)
With that said, storytellers know exactly where he is getting his idea from.
The tale is called Queen Anait, and it is from Armenia. A very capable queen teaching her king how to not die. Read it, you'll like it. The story has quite a few other versions in world folklore as well.