Seriously, look at the red logo on those sacks of cornmeal and tell me it doesn't look like a warning of danger. It looks corrosive or something. A rat comes out of the pile and starts climbing over everything & the music even changes to let you know that rats in your cornmeal isn't a good thing.
The deal is that Mr. Peterson, a local nobody, is selling the stuff for cheap and totally undercutting Hansen's price. Some townie goes by complaining that he can't afford Hansen's cornmeal & buys up a shitload of Peterson's.
Hansen is pretty much outraged when he sees people going with wagonloads of markdown meal. Edwards is a sleaze and has no loyalty to his employer - he's buying the cheap stuff too.
Later, the Boulton family sits down to dinner with TWO loaves of bread made from cheapskate cornmeal. The patriarch of this fine family is - of course - the townie from 2 paragraphs ago. He prays for the kind soul of Mr. Peterson. What a fine and excellent man he is to provide such affordable death, uh, I mean, cornmeal to this family.
Elsewhere in Walnut Grove, the Ingalls family sits down to some kind of non-deadly meal. Laura can't chew her meat because of a toothache. Pa's going to take her to see Doc Baker in the morning. & FYI, guys: "Sweets are the worst thing in the world for your teeth."
At Boulton's place, his son Paul is burning up with fever. Doc sends the father to get ice and the mother to get rags. Sorry, Doc. Looks like you're going to have to get your own rags, because Mrs. Boulton is on her raggedy, sweaty deathbed, collapsin' in the hallway.
And in case you haven't been paying attention, there's a close up of little bugs/fleas crawling in the dangerous-looking bag of cornmeal. No pic of that because, seriously, I don't ever want to see it again.
Doc makes ice caskets for young Paul and his mother. It's too late for Mrs. Boulton. She dies almost instantly. Q: How much extra freaking cornmeal did she munch down while baking the bread? A: Waaaayy too much.