If you are related to either Lady Diana, or to Prince Charles through their own line of the family prior to them being married then you will also be related to the other line as well. There are many generations of the Royal family marrying their cousins or distant cousins. The key family that ties a lot of the families together is the Cavendish family. But that is not the only thing you look at. With Royalty you look at each King and Queen as to who they married and how they are related prior.
I am related to both of them. In fact I am related to all of the European Royal Houses.
They have been marrying into eachother for centuries and are all of them closely related.
To name another example is King Christian the 9th who was called “ The father-in - law of Europe.
If you study him closer you will see why. He was the father of Queen Alexandra. One of his sons was the King of Greece, another became the King of Norway who married into the British Royal family as well (Maud) and finally another daughter who married the zar of Russia. His own wife was a German-Danish princess..( Queen Louise..)
Prince Phillip, the Duke of Edinburgh is also a member of the Royal Greek-Danish House.
Like Jeanne said, they all have been inner-marrying for centuries. Once you find yourself in thr world tree, I think almost anyone can find they are related somehow. You want to forge an alliance? Then just marry a cousin. Unfortunately, it didn't always work out, but that's what happened. That's why there were so many arranged marriages.
I did read that once a person is related to Juliana van Stolberg (mother of all Wesst-European Royal Houses, one is related to all European Royal Houses. Juliana, Gräfin zu Stolberg-Wernigerode is your 14th great grandmother. I do not know if that is right, but it seems I am, so it could be the case ?! Juliana von Stolberg, Gräfin von Nassau-Dillenburg
I don't think I am related to both lines. Princess Diana's mother, Frances Burke Roche, was my 5th cousin, and she relates back to Elizabeth Caroline Boothby(1821-1897) who married Edmund Burke Roche. She in turn relates back to my 4xgreat grandparents John Brownell (1728-1806) and his wife Elizabeth Foer. So my connection with the royal family is only by the marriage into the Burke Roche family (who probably do have royal connections) and later into the Spencer family (who of course do have many royal connections) rather than by my direct line..
Greetings, Princess Maria, pleased to meet you.
While I'm here, just calling attention to Princess Diana's pending merge:
https://www.geni.com/search/matches?id=6000000013313514628&src=...
Jennifer Lee- you need to look through all your lines. Once you find a relationship to the Royal Family there could be a lot more of them. The Key is to keep looking. YOu can look for Lady Diana's tree on line and take a look at the other trees. The Spencers, Sarah Ferguson, the Royal siblings, Gloria Vanderbilt are all 6th cousins through Lord Burghley, (William Cecil). They all relate to the Royal family through the Cavendish family. You can view the Cavendish family through the Duke of Devonshire.Go to the VISITATIONS OF DEVONSHIRE... and look through the various years of their visitations.
I don't have the tree the prove it, but DNA test on myself showed that I am within the R mtDNA haplogroup, same as the late Lady Diana Spencer.
You can view the mtDNA video at
https://drive.google.com/file/d/1Ot5gUq7U2jzyVcUp35LD8_uB0POIjMkx/v...