If you're a parent, you probably want your kids to be able to take on life's biggest challenges — with the resilience to handle whatever comes their way.

That likely means teaching them how to be mentally strong. People with mental toughness exhibit a range of traits and qualities that make them more likely to be happy, successful people, including confidence, perseverance and resilience, research shows.

Kids and adults alike can develop and hone mental toughness over time, researchers say. Here are four things parents can do to raise mentally strong children, according to psychologists and other parenting experts.

Help them empower themselves

Confidence and self-motivation are important aspects of mental toughness, which means your kids shouldn't be dependent on other people to feel good about themselves, according to psychotherapist Amy Morin.

You can help kids empower themselves by teaching them repeatable phrases that remind them "they are in charge of how they think, feel and behave — regardless of how those around them are doing," Morin wrote for CNBC Make It in 2021.

The catchphrases should be short and easy to remember, according to Morin, who is also an author and host of the Mentally Stronger podcast. She offered up these four examples:

• "All I can do is try my best."
• "Act confident."
• "I'm good enough."
• "I choose to be happy today."

Show them the value of doing something hard 

It can be tough to watch children fail at something. Still, parents need to show their kids that embracing a difficult challenge can teach them a lot — like how they perform under pressure, for example — whether they succeed or fail.

Celebrate your kids when they show the courage to take on a difficult challenge, recommends psychologist Mary C. Murphy. Help them reflect on what they learned and how they can apply those new lessons and skills going forward, she wrote for Make It last month.

Try telling your children personal stories about times when you persevered in difficult situations, and what you've learned from your past mistakes, Murphy advised. "These types of stories help normalize and show kids that almost anything worth doing usually involves a bit of struggle, especially at the beginning," she wrote.

Stay optimistic

Your attitude can be infectious, which is why child psychologists say it's important for parents to model good behavior for their children. That includes optimism, which is a key component of mental strength, according to neuroscientist Wendy Suzuki.

Optimistic, hopeful children feel more in control of their own lives and are typically more confident when taking on new challenges, educational psychologist Michele Borba told Make It last year. Optimism can be learned and taught, so remember that kids are always listening and watching for cues on how to behave, she added.

"The next time something happens, [you can say] 'That's OK, we've got this.'" said Borba. "If you keep saying it, you're actually having your kid eavesdrop on your management strategy. And the most amazing thing is very often they pick it up, and now they have a way to talk back to the worry themself."

Teach them how — and when — to apologize

A key aspect of mental toughness is emotional intelligence, which includes empathy and self-awareness. Teach your kids the importance of respecting others and themselves — including listening respectfully to others' points of view and apologizing with sincerity when they've wronged someone, Morin advised in 2019.

That doesn't mean you or your children should be constantly apologizing: Morin warned against falling into the trap of "toxic self-blame," which typically happens when negative thoughts sap your self-confidence.

Just remember that mentally tough people "take responsibility for their behavior," she wrote. "They offer sincere apologies when they regret their actions and strive to make amends whenever possible."

Correction: This story has been updated to reflect that Amy Morin is currently the host of the Mentally Stronger podcast.

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