As students return home for the holidays, there’s a mounting source of tension: They’re less and less likely to believe in God. And their religious parents may want to get used to it.

(RNS) As students return home for the holidays, there’s a mounting source of tension: They’re less and less likely to believe in God. And their religious parents may want to get used to it.

Although the majority of Americans describe themselves as Christian, the proportion has been falling for years. Nowhere is the trend more pronounced than among millennials, with each younger generation showing greater skepticism and less faith. The result is a widening gulf within families on what to believe and how to live life.

For many parents, that’s not a problem — they want their sons and daughters to form their own beliefs and will love them no matter what.

But not everyone has that attitude, and it’s more important than ever for parents to appreciate that their atheist children are still good people who deserve their support.

Fully 20 percent of Americans aged 18-25 report not believing in a god. Compare that to the 8 percent of the baby boomers and you get a recipe for holiday conflict.

Even the holiday itself is a point of contention. Pew Research Center released a survey showing more millennials now consider Christmas a cultural holiday rather than a religious one. Boomers, on the other hand, are more than twice as likely to consider it religious instead of cultural.

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People have tried to dismiss the trends. “It’s just a phase” has been the common argument. “They’ll come back to the fold once they get married and have kids of their own.”

But the data finds the opposite happening. Older millennials (born between 1981 and 1989) are hitting their 30s, and over the past seven years they’ve become 6 percent more likely to say religion is “not” or “not at all” important in their lives.

The secularizing trend is going to continue, and we’ll need to address ways for generations to continue loving and supporting each other.

One important step for parents is to understand what their children actually believe. Although the stigma is lessening every day, there are still plenty of bad associations and misconceptions about atheists.

Opening up about a lack of belief can be difficult. It’s common for young people to feel anxious, guilty or alienated. How parents respond matters.

Openly Secular, a project started in 2014, designed a variety of resources to help parents, including “Opening Minds, Changing Hearts: A Guide to Being Openly Secular” and “Your Child Is Secular … Now What?: A Guide for Religious Parents of Secular Children.”

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The conversation can sometimes be difficult, but it can also bring you closer together.

If your children tell you they’re atheist, take the time to ask them about their beliefs. And then listen. Instead of hearing that they hate God or have no values, I expect you’ll be impressed at how thoughtful and considerate they are.

Not believing in God doesn’t mean that your son is immoral; it means he helps others simply because he cares about them as fellow human beings. Not believing in an afterlife doesn’t make life meaningless for your daughter; it makes her consider this life all the more important to cherish.

Hundreds of Secular Student Alliance communities are thriving on high school and college campuses, providing a place for students to explore and live their secular values.  Whether it’s by volunteering for food banks or raising money for charity, they’re doing what they think is right.

Coming together as a family is one of the great joys of the holidays. It should be an occasion of love and togetherness. Your children have become adults, forging their own beliefs, their own identities and their own lives. They should be celebrated and respected for who they are.

Even as a staunch atheist, I find that this biblical passage resonates with me: “Love always protects, always trusts, always hopes, always perseveres” (1 Corinthians 13:7).

Parents: Love your children, whether they share your faith or have left it.

(August Brunsman is executive director of the Secular Student Alliance)