Many British peers have more than one title. When this happens, the heir’s peer is usually allowed to use a lesser title of the peer as a courtesy title. For example, Prince Edward is the Earl of Wessex. One of his lesser titles is Viscount Severn, which is used by his son.
Current plans are for Edward to eventually be created Duke of Edinburgh after the title merges in crown. When this happens, will James (his son) be “promoted*” to Earl of Wessex?
Zev Steinhardt
It’s not really a promotion, of course, because the title is not his and he not a peer.
Also young Lord Severn is really “HRH Prince James of Wessex”. His parents requested that their children only be styled as children of an earl, not male-line grandchildren of the soveriegn, but the Queen never actually changed the letters patent granting them “HRH status”. So Lord Severn and his sister, Lady Louise, can still decide they want to use their royal titles if they grow up.
That’s what I meant, but really, nothing would actually stop him from making one up and insisting on it. Heirs to earldoms and above who don’t have access to a suitable courtesy title do it.