Yes, they were very explicit about blizzards and "if you lie down you'll never get back up," they didn't find people until spring, stuff like that. She's also very honest and descriptive about her sister going blind, and other sad events that you might think a children's book author of that time period would have avoided.
I read a biography of her later, and it turned out there was a whole year of her family's life that she didn't even mention--the fact that her mother had a baby boy who died within a year, for example. But in general, everything she describes in those books is borne out by later research. Just makes me appreciate them even more; I'm very glad I read them all.
"This disturbing warmth is another common sensation in advanced hypothermia. Right before the end, the skin may feel like it's on fire.... Doctors are not sure why this happens.... Whatever the cause, the result is that victims of hypothermia suddenly feel so hot and stifled that they strip off their clothes....
"It sounds bizarre—to wantonly sacrifice warmth and cover just when you need it most—but it's common enough that doctors have given the impulse a name: paradoxical undressing. Before paradoxical undressing was identified, police routinely mistook hypothermic women with torn or missing clothing for victims of sexual assault. The reaction explains a disturbing incident in military history. After a brutal three-day storm in January 1719, hundreds of Swedish soldiers were found stripped and dead in the field in the wake of a disastrous campaign against Norway. At the time it was assumed they had been plundered by their comrades, but now doctors believe that they tore off their own clothes as their minds and bodies went mad with cold—a mass outbreak of paradoxical undressing." —David Laskin, The Children's Blizzard (New York: HarperCollins, 2004), 193–194