Am I the Only Film Viewer in History to Notice? Or Wonder?

In the 1944 film National Velvet, based on the 1935 book by Enid Bagnold, a story appears about a horse named Moifaa swimming from a shipwreck and being rescued from an island. This story IS in the original book, pages 205-206 of the Dover Children's Classics paperback edition and pages 173-175 of the 1985 hardcover Golden Anniversary Edition from William Morrow and Co. Donald hysterically insists the horse died on the island when in fact he was rescued and survived to win the Grand National. 

(According to this http://www.grand-national.net/moifaa.htm, Moifaa was a real horse which won the Grand National in 1904, but it was not he but another horse in the same race which was one of two horses to survive a 1901 shipwreck, not near Ireland as the book says but off the Cape of Good Hope, closer to the site of the wreck in The Black Stallion.  The movie National Velvet does not give a location for the wreck.) 

So possibly both Enid Bagnold and Walter Farley were inspired in their books by the same true horse shipwreck survival story, but...isn't it just a BIT WEIRD and STRANGE that:
--In the book, Velvet Brown tells the story to her brother Donald, saying she heard it from Mi Taylor.
--In the movie, Mi Taylor, played by Mickey Rooney, tells the story directly to Donald.
--In the book story, some fishermen see the horse, but leave, frightened, and someone else rescues the horse. In the movie, fishermen rescue the horse.
--35 years later, Mickey Rooney appeared in the film The Black Stallion, with a plot identical to this story--a horse is shipwrecked, swims to an island, is rescued by fisherman, and goes on to win a big race--and aren't National Velvet and the Black Stallion movies the ONLY horse movies in which Mickey Rooney EVER appeared?  Am I the only one EVER to notice this and find it all just a bit odd?  Sorry if this has been said but if so I couldn't find it! 