PS The biggest conundrum in the world of espionage is why are the exploits of its fictional characters more popular than the real thing.
Because people like things that mimic life, while actually being removed from it. There are those who prefer non-fiction over fiction, but more prefer the "escape" from their daily lives. That's why sci-fi is so popular - and sci-fantasy, or urban fantasy. With the fantastic, one knows it cannot be real, but with the fictions, it just maybe could be possibly something that might maybe happen. It's all related to suspension of disbelief.
@ Hilary and anyone else following along the Llewelyn trail -- Desmond now has his only sibling. (And, BOY, did I have to work to find her death!) She married once, had one child (who married), but I think the child is still living. The ex-husband married a second time before he died, but that was in England.
I have not done anything more, yet, with Desmond's uncle Leonard and his wives, and the second wife's 3 husbands, because I got all tied up trying to find his sister's death reg. (Wrongly named.) I have no idea how to find divorces in England, so I covered that with what sourcing I could. (I *think* it was a bankruptcy hearing, or an appeal to be discharged from it.)
I am hopeful that something will be found that can make a connection to the Tree, but whether in Wales, or England, is yet to be seen.