There's a phrase that I hear parents say all the time: "I just want my kids to be happy."

But as a child psychologist and a mother of three kids, I've seen how optimizing for happiness, instead of resilience, in childhood can do more harm than good.

Of course, I don't want my kids to be unhappy. But when we make happiness the goal, we start to see our kids' distressing feelings as problems to fix, rather than emotions to tolerate. And when we struggle to sit with our kids' hard feelings, we unintentionally teach them that those feelings are bad, or even threatening.

Over time, they learn to avoid distress instead of managing it. Kids can't learn to tolerate feelings that we don't tolerate in them. The more we focus on making our kids happy, the fewer feelings they learn to cope with.

And that's a recipe for anxiety, fragility and self-doubt, which pretty much leads to them becoming unhappy adults.

Teach your kids how to be resilient

Happiness doesn't come from avoiding hard feelings — it comes from learning how to tolerate them. The more we help our kids cope with distress, rather than trying to make it disappear, the less space those distressing feelings take up.

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In other words, building resilience in childhood makes room for happiness to emerge naturally, from a place of feeling at home with oneself, not from avoiding hard stuff at all costs.

The next time your child is upset, consider these tips to help them build resilience:

• Regulate yourself. One of the biggest reasons we swoop in is because we feel uncomfortable. It's almost as if we confuse our kid's feelings with our own. Use this mantra: "I'm safe, this isn't an emergency, I can cope with this."
• Sit, don't fix. Sitting with your kid's feelings could mean saying, "Yes, it makes sense that you're feeling that way," or, "Ugh yes, I get that," or, "I'd feel the same way." It also be you nodding slowly, rubbing their back, and saying nothing.
• See your kid as capable. Reminding yourself that your kid can handle tough emotions means you'll be less likely to provide a quick exit ramp. When you stay calm in your kid's storm, you're modeling resilience — and they'll absorb it from you.

Resilience will set your child up for future success

When we focus on keeping our kids happy, we inadvertently send the message that distressing feelings — frustration, sadness, anger, jealousy — are dangerous. Instead of sitting with these emotions and working through them, kids learn to avoid or fear them.

Fast-forward to adulthood, and these same kids are now adults who feel unprepared for life's inevitable challenges. Worse, because their bodies are so unaccustomed to distress and so conditioned to chase happiness at all costs, they avoid challenges, shy away from new experiences, and struggle to bounce back from failure.

So, no, I don't just want my kids to be happy. I want something deeper, something sturdier: I want my kids to feel at home with themselves, no matter what life throws their way. I want my kids to be resilient — which, ironically, is the foundation for true happiness.

Dr. Becky Kennedy is a clinical psychologist, mom of three, and the founder and CEO of Good Inside, parenting company and next-generation movement. Through her bestselling book, "Good Inside: A Guide to Becoming the Parent You Want to Be," TED Talk and podcast, she has built a community of millions of parents who turn to her for practical, sturdy and compassionate advice.

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