Similar to the Stoker thing is the way Simon Wells, H.G.'s great grandson, directed the 2002 film of The Time Machine. Not spot-on, but close.
The reason I brought this up was that I’d noticed all these cases where sereies had been continued, or sequels written by people who were relatives (usually children of) the original author, or close friends of the author. There wasn’t any obvious reason why they should have been chosen, aside from this connection. They weren’t noted writers of that sort of thing before that, and it seems like a leap of faith (or the hope of marketing over reality) that the work will measure up or be at all similar.
Michel Verne, Jules Verne’s son, is hated by Verne purists, because he altered hios father’s work after Jules’ death, sometimes trying to pass off his own work as that of his famous father (as with The Barsac Mission, or adding extra chapters (as in The Meteor Hunt) or making significant alterations (he changed the setting of The Secret of Wilhelm Storitz by a century!) It’s only in the last decade that unaltered versions of many of these works have become available in English.
Verne the younger has a different style than his father, and he’s more adventurous, willing to include in his stories advances far beyond what was his present-day technology. I think he deserves better of SF critics, myself, even if he did alter The Master’s works without acknowledging this. The point is, Michel Verne really wasn’t the ideal one to continue the Voyages Extraordinaire, even though he was the son, and a writer. (Not that anyone really wanted to – sales of Verne’s later books were dismal, and the last few weren’t translated into English until a few years ago).
The recently-late Anne McCaffery’s son Todd took over writing her Pern novels. There were a few “joint” books, since then it’s just the son. I haven’t read any of them, but I understand they’re not nearly the abominations-before-the-Lord that Herbert’s foul progeny has churned out.
I’d forgotten about that. No, they’re actually pretty good. The “voice” is noticeably different, but it’s different, not painfully stupid like the new “Dune” books. I very much enjoyed Todd McCaffrey’s Pern novels.
Anther example comes to me – James Blish’s wife J.A. Lawrence finished up the novelization of the original Star Trrek episodes that he’d been writing, completing Star Trek 12 and Mudd’s Angels (which included an original story by her). She’d written some original SF before that, but as far as I know, nothing like the Star Trek stuff. She’d co-authored one story with Blish (for Again, Dangerous Visions, no less!), but they didn’t have a reputation as a husband-and-wife team like Henry Kuttner and Catherine L. Moore.
The Oz books were continued by, among others, John R. Neill, the main illustrator of the series. Don’t know how friendly he and L. Frank Baum were, but my hunch is they count as “friends.”
In comic books, I would only count the creator-owned ones as a concern for this. Jack Kirby’s son took a stab at continuing either Silver Star or Captain Victory after his father’s death (The series had lain fallow for a couple of decades) to no particular acclaim. Steve Gerber, after he quit writing Destroyer Duck, stayed on as editor and got his buddy Buzz Dixon to write an issue or two; this was not successful.
According to the Eric Van Lustbader wiki, he had the permission of Ludlum’s estate. Any more connection than that, I do not know. I had a brain fart between reading and posting, and forgot that was part of the requirement of the OP.
I didn’t know about this. I was familiar with the extensions by Ruth Plumly Thompson (AFAIK, neither a friend nor a relative), but hadn’t heard of Neill’s volumes.
Whether this fitsd the OP case or not gets into legalistic hair-splitting. I suspect that I’d lump this in with Sagendorf taking over Popeye, bevcause it’s someone associated with the series, not someone who was dragged in because of familiarity with the author, but YMMV. My aim in starting this thread wasn’t to score points in some game, but to learn about other parallel cases.
In another direction (and, again, not quite the same as the OP), Emmett Kelly’s son Emmett Kelly, Jr. carried on his father’s character of “Weary Willie”. Actually, he didn’t do it at the urging of any Powers That Be – he did it on his own, while his father was alive and still performing, and the elder Kelly didn’t like it (I suspect he didn’t like his son stealing his act – clowns are territorial about their makeup and routines).
It reminds me of how Lon Chaney didn’t want his son going into the acting business. But young Creighton did, changing his name to Lon Chaney, Jr., and I’m sure the folks at Universal were glad to have another Lon Chaney playing grotesque characters for their horror films. But the younger Chaneyu’s style wasn’t at all luike his father’s, and the only type of role I know that they both played was a vampire, but in completely different ways:
(Interestingly, the elder Chaney was a syrong candidate for plaing the Frankenstein monster, but he died before that film was made. Lon, Jr. played the monster twice for Universal (once unofficially and uncredited), and later played him on television.)
Pretty clearly the Chaney’s don’t fit the OP at all.