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Try doing something kind for someone “just because” — i.e. not because it’s their birthday, or a holiday, or an anniversary — and you’ll likely find them scratching their head, wondering whether something’s gone awry.

That’s what happened when Maria Shriver, the 63-year-old author of I’ve Been Thinking …Reflections, Prayers, and Meditations for a Meaningful Life and host of the new podcast Meaningful Conversations with Maria Shriver, received an out of the blue affectionate text from son Patrick Schwarzenegger. “My son last week sent me a note that said, ‘Hey! Just wanted to check in on you and say, ‘I love you,’” she told People. “And I was like, ‘Do you need something?’ and he was like, ‘No.’ I was like, ‘[Do you] want something?’ and he was like, ‘No.’”

After interrogating the potential reasons for his surprise text, she let the pleasure of the experience sink in. “He was just sending me a text to say he loved me and it changed my whole day,” Shriver told the magazine. “I was like, ‘Wow, that is such a gift, thank you.’ If you had asked me at 20 if that is what would make me feel loved I would be like, ‘What?!’ But these are the things that one learns and brings you peace.”

Experts agree that unexpectedly checking in with loved ones provides benefits beyond a happy surprise:

Unexpected check-ins are more powerful than planned ones

Sonja Lyubomirsky, Ph.D., a psychology professor at the University of California, Riverside and author of The How of Happiness, tells Thrive Global that Schwarzenegger’s unexpected check-in was particularly powerful for its sweet spontaneity. “Acts of kindness are more powerful when we do them spontaneously because it means we are not doing them for some strategic reason (e.g., to get the other person to like us or to reciprocate later),” she says. “When acts of kindness are done ‘just because’, they are more likely to come from the heart.”

Checking in “just because” can help someone who’s silently struggling

The importance of surprise check-ins with our loved ones was thrown into harsh relief last summer when celebrity chef Anthony Bourdain and fashion designer Kate Spade died by suicide. A clarion call sounded across social media platforms urging all of us to check in on friends and relatives, “just because,” even if they haven’t exhibited signs of distress, because you never really know what someone is up against, or whether they’re silently struggling.

“Our brains are hardwired to connect with one another,” says Dawna Markova, Ph.D., a cognitive and educational psychologist and author of Reconcilable Differences: Connecting in a Disconnected World, but we tend to retreat into our individual orbits to avoid social judgement from one another, especially if we’re struggling with mental illness, she says. “Go back to what’s innate,” she encourages: “Reach out and ask a simple open question like, ‘What’s it like to be you right now?’”

Like Schwarzenegger, you’ll make the person feel loved and less alone in the world.

A spontaneous act of kindness benefits our own happiness, too

Shriver wasn’t the only one to benefit from Schwarzenegger’s surprise note of affection. Several studies indicate that he’ll reap rewards related to his own mental health for acting on his love and affection. Myriam Mongrain, Ph.D., a professor of psychology at York University who studies compassion and well-being, tells Thrive Global: “Random acts of kindness have been empirically related to boosts in happiness,” she says, citing one of her studies on the practice’s power to alleviate symptoms of depression, and another on how compassion boosts happiness and self-esteem. (Research indicates that expressed affection also improves happiness, self-esteem, and relationship satisfaction.)

“The reason it makes us feel good may lie in its self-transcendent properties,” she says. “For a moment, we are free from our own worries and preoccupations. Making life better for someone is highly rewarding and probably has served an important evolutionary function.”

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