Constitutionally there is no such thing as a BRITISH Royal Family. Elizabeth II is Queen of England and simultaneously Elizabeth, Queen of Scots. Charles is Prince of Wales. i.e. the highest Ranking person in Wales. When Charles takes over he will be King of Scots and Charles ?? King of England, while William will become Prince of Wales.
Someone pointed out that the Sussexes are seldom seen in Sussex, but I can't remember when the Duke of Edinburgh last appeared in Edinburgh. The whole titles thing is a farce. Nothing to stop us commoners naming our children as Little Princess Kylie, or Robert King (like the lad from school who was always referred to as King Robert).