The rules, the real ones, have seldom been written down, yet every girl knows them. (The boys who babysit don’t, by the way. They eat too much, they leave messes, they break vases while roughhousing with the kids, but the children adore the boys who babysit, so they still get invited back.) The rules are intuitive, as are most things governing the behavior of teenage girls. Your boyfriend may visit unless it’s explicitly forbidden, but the master bedroom is always off-limits, just as it would be in your own house. Eat what you like, but never break the seal on any bag or box. Whatever you do, try to erase any evidence of your presence in the house by evening’s end. The only visible proof of your existence should be a small dent on a sofa cushion, preferably at the far end, as if you were too polite to stretch across its entire length. Finally, be careful about how much food you consume. No parent should come home and peer into the Pringles can—or the Snackwell’s box or the glass jar of the children’s rationed Halloween candy—and marvel at your capacity. There is nothing ruder than a few crumbs of chips at the bottom of a bag, rolled and fastened with one of those plastic clips, or a single Mint Milano resting in the last paper cup.

Terri Snyder, perhaps the most in-demand babysitter in all of River Run, knew and followed all these rules. Once when she was at the Morrows’ house, she discovered a four-pound can of pistachio nuts and got a little carried away. And while the canister was so large that it provided cover for her gluttony, the shells in the trash can left no doubt as to how much she had eaten. To conceal the grossness of her appetite, she packed those shells in her knapsack and the pockets of her ski jacket. Riding home in the front seat of Ed Morrow’s Jeep Cherokee, she realized she was rattling softly, but Mr. Morrow seemed to think it was the car’s heater. The next time she babysat for the Morrows, she found another canister of pistachios, a sure sign of trust. . . . Read More.