Creative Differences: Initial producer Ed Friendly wanted the series to remain true to the books, but Michael Landon was against the idea of cast members going around barefoot in the wild - and of sporting the enormous beard Charles had in the books (neither he nor NBC wanted to hide his face from his fans). Thus, although every episode was "An NBC Production In Association With Ed Friendly," it's clear who the real man in charge was.
He Also Did: Rose's friend and the writer of the "Rose Years" book series, Roger Lea Mac Bride, ran for President under the Libertarian Party ticket.
One Steve Limit: Unmentioned in the book is the fact that Almanzo had a third sister, also named Laura. To avoid confusion with protagonist Laura Ingalls, Laura Wilder was omitted from the books and replaced by Eliza Jane. (In Real Life, and for much the same reasons, Almanzo nicknamed Laura Ingalls "Bess" for her middle name of Elizabeth.)
The Other Darrin: Bonnie Bartlett played Grace Snider Edwards in seasons 2 and 3. When the character appeared for one episode in season eight, she was played by Corinne Camacho.
In the same season eight episode, David Kaufman played Carl Sanderson Edwards, when the character had been played by Brian Part during the second and third seasons.
Woody Eney played Almanzo's brother Royal Wilder in "The Nephews" in season seven. When the character returned in "Times Are Changing" in season nine, he was played by Nicholas Pryor.
Science Marches On: Mary's blindness is blamed on scarlet fever in the books. Modern studies suggest that she had contracted meningoencephalitis, a type of brain inflammation, which caused her blindness. The 'scarlet fever' diagnosis was probably a misdiagnosis, common back then.
And the "fever 'n' ague" everyone comes down with in Indian Territory is blamed on bad watermelons by Ma and Mrs. Scott and on "breathing the night air" by Pa, but by the end of the chapter both theories have been proved wrong and the book explains, "No one knew, in those days, that fever 'n' ague is malaria, and that some mosquitoes give it to people when they bite them."
Serendipity Writes the Plot: When the series started, the show's producer had signed an agreement that when the show ended, the site of the town would be returned to its original state. When filming the series finale, they were faced with the cost of demolishing the buildings. Michael Landon had the idea of blowing them up with dynamite, making them easy to haul away. He then wrote the memorable final scene where the townsfolk blow up their own town to accommodate the real-life demolition.
Technology Marches On: Although filmed in the 1970s and 1980s, these stories – set 100 years earlier – give viewers a representation at some of the early workings of technological marvels of the Age of Invention, as the 1870s and 1880s were arguably an era where discovery and invention was at its peak. Everything from "talking machines" (an early-type sound recorder that can replay the human voice) to the telephone is seen in its earliest forms. Additionally, although it has nothing to do with technology so much, a form of the trope can apply to sports-related episodes; as such, viewers can see an 1870s-form of baseball, football and professional wrestling, all of them novel during the post-Civil War era.
Written-In Infirmity: Alison Arngrim broke her arm right before filming of the episode "Bunny" was to begin. Since her character, Nellie, was injured in the episode anyway, the broken arm was incorporated into the script as an additional injury. Arngrim wore nineteenth-century style wrappings to cover her very real 1970s cast.
Averted in the episode "Be My Friend". Melissa Gilbert had broken her arm. Shawls and camera angles were used to hide the cast.