Ask any married couple that’s been together for many years what their secret of happiness is, and they may offer a few expected answers: shared values, a common faith, the comfort of many years piling up one after the other that offer security and familiarity — or their shared joy in experiencing generations of family together.

But the one thing most successful couples will probably mention — with a sparkle in their eyes?

Laughter. That couple you admire has been able to laugh together about things both big and small.

They have found themselves in fits of laughter about something maybe no one else on earth can understand. They have caught one another’s gaze and grinned, sending a silent message to the other: Did you catch that? Wasn’t that hysterical?

These couples have a sort of invisible thread of laughter and merriment that makes a few moments of even the toughest days worth experiencing as a team.

The American humorist and author Mark Twain once said, “The human race has one really effective weapon, and that is laughter.”

It can also be a powerful marital tool, soothing the rough spots,  increasing connection during stress, and contributing to a relaxed outlook that enhances any husband-wife connection.

Laughter is good for couples for many reasons.

First, laughter is good for the body. “Laughter strengthens your immune system, boosts mood, diminishes pain, and protects you from the damaging effects of stress,” notes Helpguides.org.

Laughter triggers the release of endorphins, the body’s own feel-good chemicals. Endorphins create a sense of well-being and can even temporarily relieve pain.

Laughter improves the function of blood vessels and increases blood flow, “which can help protect you against a heart attack and other cardiovascular problems,” notes Helpguides.org.

Second, shared laughter creates an instant bond and eases tension, especially in relationships.

“Sure,” you may say, “I know laughter is important. But my spouse and I are two busy people with very intense careers, and our free time is chewed up by kids’ activities, household chores, and other obligations. How do we start to laugh more — it’s not that simple!”

Isn’t it? It all starts with a mindset.

Like any form of self-improvement, laughing together takes practice, learning to recognize and cull the “funny” from life. Tell yourselves out loud that you will take time to laugh together. Start with a funny movie and just wait until you hear yourselves laughing together; it will be something you’ll want to do again.

Here is a list of classic comedies that can’t help but get you grinning together.

Adopt a schedule that allows for relaxed time together, which fosters laughter.

You know that couple you’re secretly jealous of every time you encounter them? While you’re stressing about making the playdate and doing the week’s shopping as you tear downtown to pick up the dry-cleaning, you run across them — enjoying coffee together at a coffee shop, dressed in their sweatpants, sipping coffee and seemingly laughing over nothing.

They are fun to be around because they know what fun is.

You know the only thing that separates you from them? They made the time to do nothing, which is a great petrie dish in which to grow laughter.

That couple also has errands and kids and busy schedules, but their priority — at least for an hour or two a week — is simply laughing together. They’re taking time to enjoy each other’s unique personality and that shared goal of relaxation that fosters deeper interdependence.

Check out these tweets from married folks, collected by Yahoo Lifestyle, that show a relaxed and humorous take on the ties that bind.

Made it to that level of marriage where you get in trouble for being able to fall asleep so fast.

— Simon Holland (@simoncholland) September 23, 2018

If your husband unloads the dishwasher and you don’t notice right away, don’t worry, he’ll remind you.

— Nonchalant Charlotte (@jellybnbonanza) September 23, 2018

It’s fall. Let the thermostat games begin.

— Housewife Plus (@housewife_plus) September 22, 2018

Him: I’m feeling under the weather.

DATING: I’m so sorry. That stinks.
ENGAGED: I will nurse you back to health with chicken soup and cuddles.
MARRIED: *sprays him with lysol*

— Jesspacito (@mommajessiec) October 1, 2018

Shared laughter, at its essence, celebrates friendship.

Real friends laugh together, and when you laugh with your spouse, you are connecting back to that deep sense of friendship that brought you to the altar.

And if it’s used regularly, as a valued tool in your relationship toolbox, laughter will help keep you on the right course — together.

Check out this bride who can’t stop laughing during her wedding, below!