"Fool and genius after all" (or more naturally: "A fool and a genius really are...")

The protagonist got married half a year ago and moved out of their parents' house. After a long time, their older brother calls, and as the conversation progresses, the siblings decide to play an online game together while on the call. They play the game in a friendly atmosphere while exchanging updates and having sibling squabbles, but the older brother is shocked by something said just before the game ends. ※Consists almost entirely of dialogue. The younger sister's husband is set as a researcher. To the siblings, researcher = genius, so there are no genius episodes or the like in the story. A participating work in the Narou Radio Taishō 4.