For generations, amateur marriage counselors and meddling in-laws have passed down a simple piece of wisdom: If you want to know what your spouse will look like in 30 years, look at their parents. It’s a comforting little proverb, because it suggests that the mysteries of aging can be solved by squinting at your future mother-in-law while she eats potato salad at the family barbecue.

But like all folk science, this adage deserves an update. Parents only show you the mid-game of aging. The real long-term forecast lies in the grandparents. Parents might show the first creases, the first silver hairs, the first alarming comments about “kids these days.” But grandparents? They show you the endgame. They are the long arc of the genetic story—the blueprint of bone structure, hairline survival rates, and whether your spouse will keep that twinkle in their eye or develop a permanent scowl that could curdle milk.

Why the Grandparent Upgrade Matters

By age 40, most of us are a blend of genetics, lifestyle, and regret. Diet, exercise, sunscreen, and whether you lived through the disco era all leave their marks. Parents reflect this messy middle ground. But the grandparents? They are what’s left after time and circumstance have played their final cards. They’re the “control group,” stripped of fads and fitness trackers, still carrying the echoes of the raw DNA.

In other words: if you really want a sneak preview of your spouse’s face at 75, don’t look at their mom or dad. Look two generations up. That’s where the future is hiding.

The Joke’s on You Anyway

But here’s the thing—why does it matter? By the time you’re both in your 70s, you will also be frumpy. You’ll both be shuffling around the house in orthopedic shoes, squinting at the thermostat, and wondering if it’s worth the effort to bend down and pick up that sock. Your spouse’s wrinkle pattern will be the least of your concerns.

That trim jawline you once admired? It’s gone, replaced by a shared affection for early bird specials. Those eyes you thought sparkled? They’re now hidden behind bifocals smudged with fingerprints. If you’re lucky, you’ll both have matching pill organizers and a shared cardiologist.

In fact, the entire fixation on “what they’ll look like when they’re older” rests on the mistaken assumption that you’ll be different. Newsflash: you won’t. The frumpification of aging is mutual. And, paradoxically, that’s the most romantic part of all.

The Real Adage We Need

So let’s retire the outdated proverb. Looking at parents for signs of future beauty is like checking the weather app for what next year’s summer will feel like—an exercise in misplaced confidence. Looking at grandparents is more accurate, but also equally pointless.

Instead, here’s the new wisdom we should pass along:

“If you want to know what your spouse will look like at 70, just remember—you’ll both look like 70-year-olds. And if you’re lucky, you’ll both still be there to laugh about it.”

That’s the truth hidden beneath all the folk advice: marriage isn’t about choosing someone whose genetics will still look good in old age. It’s about having someone to complain about Medicare paperwork with, to split a slice of pie at the diner, and to shake your heads at teenagers who wear sweaters in the summer.

Because at the end of the day, the grand prize isn’t beauty. It’s companionship in the long, inevitable march to frumpiness.