Deliberate mistake: In the opening of seasons 2 onwards, there is a photo of Olivia outside the Church with the family. This is a scene from Season 1 Easter Story. However, it had to be from an outtake because the position of Erin, the absence of Jason, is different than what is shown in the episode. It's just something I noticed when I identified from where the shot was taken.
Other mistake: During almost any random episode of the family hanging out on the porch after dark, the moonlight is unusually bright, indicating obvious studio lights in their faces, or plug-in lamps on extension cords for actual light attached to the porch ceiling or whatnot.
Factual error: Considering it is the Depression, it is highly unlikely that the family would have any electricity in The House. With maybe the exception of a lamp or two, as rural folk typically didn't have such accommodations in 1930. Yet every room has some form of fancy lighting display.
Other mistake: Maryellen wears visible eyeliner throughout the show, despite being during the depression. She wouldn't be wearing any makeup.
Suggested correction: Why wouldn't she be wearing makeup during the depression? Especially if it was just a small amount. This isn't a mistake, just your opinion. Women continued to wear makeup during the depression, and not just starlets or the rich and famous. In fact, makeup sales overall hardly took a dip during the depression because women through the US were still buying it.
Despite that women did wear it during the Depression, part of the factor being that the Waltons wouldn't afford such a luxury, considering their very tight pockets. Otherwise, we'd see Olivia preening herself also, before she goes anywhere. But doesn't even wear lipstick. And Maryellen is never 'caught' actually putting on the eye makeup. So it's likely not any opinion.
