cepe
Majesty
- Joined
- Mar 5, 2012
- Messages
- 6,333
- City
- London
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- United Kingdom
The Dukedom of Edinburgh is a future possibility for Edward. Not carved in stone. The statement on any future children addressed the fact he's an earl.
But since you gain titles and not lose them, Edward would still retain his current peerage if granted a dukedom. So Louise stays a Lady no matter what. James would have an option I suppose between viscount and earl.
As any title is honorary, then I think the decision would be with Edward. Custom and practice is that the son of a Duke uses the Earldom as his honorary title.