Exactly like the title says, a story where a father's biological son and adoptive son fall in love, preferably only after just meeting as adults rather than being raised together. Extra points if the biological son is the biggest of the two.
I've seen a lot of people describe the golden trio's secondary houses as JK Rowling's way of featuring representatives from all three remaining houses without straying away from the Gryffindor POV, and while I agree to a certain degree, the idea that Ron stands as Hufflepuff's representative has never sat right with me.
I think it's gotten popular due to the fact that a lot of people look down on Hufflepuff, both in and out of universe, and some fans like to think of Ron as the lesser of the three.
Here's the problem though; while Ron *is* very loyal, and often underestimated, both by others and himself, I wouldn't necessarily describe him as wiser than the other two, nor would I *ever* desrcibe him as particularily patient or hard-working, so here's the correction I bring to this theory;
In the first book of the series, we are introduced not to three, but to *four* children with very distinct personalities, all sorted into the house of Gryffindor. Out of these four, three of them *outright* mention that the Sorting Hat hesitated between Gryffindor and a respective house in each individual case.
Harry Potter:
This is one of the two easiest ones. The Sorting Hat hesitating between Gryffindor and Slytherin literally stands as a major plot point in the second book, where it literally asserts that he still believes Harry would have been more at home there due to his personality and strengths.
Hermione Granger:
Another very easy one. You could probably tell that Hermione also could have made an excellent Ravenclaw without even remembering that she herself mentions after the sorting ceremony that the hat hesitated between the two.
Here's where things get interesting, because there *is* one character who's looked down on, both by others and himself, even more than Ron is. One character who challenges the other three despite his insecurities, out of loyalty, not to them, but to their house. One character whose patience, gentle nature, and most of all hard work far exceeds Ron's, Harry's, and Hermione's:
Neville Longbottom:
Neville embodies every aspect of the Hufflepuff house to a tee. Not only this, but he himself *also* mentions that the Sorting Hat hesitated between the latter and Gryffindor before making its choice, as well as taking the place of Professor Sprout, the head of Hufflepuff, as Herbology teacher after she retires, which, even though it probably doesn't make him head of Hufflepuff since he was never sorted into it, definitely feels like a parrallel.
Which only leaves...
Ron Weasley:
Regardless of whether or not he's any braver than the other three in the abstract grand scheme of things, Ron is scrappy, hot-headed, impulsive, often gets into fist fights, and always jumps in head first to defend the other two, more often than not, at his own expense. He is, conventionally speaking, the most outwardly courageous of the group, and I think a lot of fans have trouble admitting this because of how they view him, considering Gryffindor tends to be presented as the "best" house (I honestly think this series may have been better if all four had actually been in different houses, with four different povs, but I guess being locked in Harry's, sorting them in the same place was the best way to give the story easy access to all of them as often as possible). Harry doesn's chose Gryffindor over Slytherin among the three remaining houses randomly, he choses it *specifically* because it's Ron's house. Ron and Malfoy *literally* stand as contrasts to one another and each of their respective families' values. We can even see parrallels between the way Godrick Gryffindow and Salazar Slytherin were described as being "the best of friends" and Ron and Harry's friendship.
All in all, this probably doesn't matter much, and it isn't to say that Hufflepuff is lesser in any way, Neville rules, but I think a lot of people's perceptions of Ron are limited to seeing him as the overlooked one, or the loyal sidekick lacking most of Hufflepuff's strengths, rather than the hot-headed and often fool-hardy, but also ultimately fiercely courageous, brawny, outspoken member of the main cast. Food for thought I guess.