Congratulations. Two months ago, your kid graduated from college, bravely finishing his degree rather than dropping out to make millions on his idea for a dating app for people who throw up during Cross Fit training. If he’s like a great many of his peers, he’s moved back home, where he’s figuring out how to become an adult in the same room that still has his orthodontic headgear strapped to an Iron Man helmet.

Now we’re deep into summer, and the logistical challenges of your grad really being home are sinking in. You’re constantly...