Dec. 5--For millions of Americans, December is an extended toast to every holiday's highlights. Christmas is coming. The feast of Eid al-Fitr, concluding Muslims' month-long Ramadan fast, is this week. Hanukkah's final candles are lit Friday. Sunday is Bodhi Day, marking the anniversary of the enlightenment of the Buddha.

But when religious pluralism hits home--22% of U.S. households now have more than one faith under one roof--the party's over for a growing number of families. Divorce is three times more prevalent in interfaith families with children than in same-faith households, according to the first national statistical look at the issue.

The American Religious Identification Survey 2001 (ARIS) finds that of all U.S. adults who have had children with someone of another faith, 10% are divorced, compared with 3% for parents of the same faith.

The finding emerged as demographers looked in depth at the survey's findings on the religious and spiritual choices of 50,000 people. Researchers from the Graduate Center at City University of New York were the first to ask people not only their own religious identity but also the faith of their current or former partner--and to ask how parents of differing religions were raising their children.

Few were surprised to add up 28.4 million Americans living in mixed-faith households, says Ariela Keysar, one of three co-authors of the survey. Couples come in more flavors than Lifesavers: Baptist/Methodist, Catholic/anyone, Jewish/Episcopalian, faith/no faith.

But the decisions they make for their children are not simply a private matter between each household and their higher power. The aggregate effects of parents' religious choices--from prenuptial negotiations through marriages and divorces--radiate across society as faith-based values guide belief and action in politics, education, health and ethics.

The survey found each interfaith household may cost religious denominations three to six future adherents when parents choose one faith, or none, for their children. Catholic parents in interfaith marriages are among those most likely to say their kids are being raised in their faith (66%). But retention rates drop to half for Lutherans (54%) and Methodists (51%) and less than one in three for Episcopalians (31%).

A 1990 study by Keysar, Barry Kosmin and Egon Mayer, the baseline for their 2001 survey, didn't asked these marriage, divorce and upbringing questions. "So it may be another 10 or 20 years before we can see which groups will gain or lose," Keysar says.

Those falling numbers alarm groups such as Southern Baptists who believe children must learn one absolute truth about God and minorities such as Jews and Muslims who fear assimilation or seek the clout that comes with growing numbers to increase their influence in the public square.

Ibrahim Hooper, spokesman for the Council on American-Islamic Relations, says Muslim men, who are permitted in their religion to marry outside the faith, have trouble in custody disputes in U.S. courts. They are responsible for raising Muslim children, he says, but "we find the father's faith and ethnicity are used against him."

Often two distinct faiths can only work together if parents ignore theological gaps between divergent beliefs about the nature of God, the value and role of scripture and the path to salvation.

If Methodist Mom says all good people go to heaven, but Baptist Dad says salvation is only through Christ, it can be a ticket to confusion or indifference for kids, says religion researcher George Barna.

He says children need one faith because, "Without it, you wind up without an anchor, a community and a worldview for making decisions internally and eternally." But millions of Americans say mixing it all up works just fine.

So far, mental health experts have seen no lasting psychic misery inflicted by growing up with parents who take opposite stands, says Los Angeles attorney Marshall Zolla, a family law specialist.

Ed Johnsrud, whose grandparents came from a tiny Scandinavian fundamentalist Christian sect, married Patti Oblath, a Jew, and promising to raise children as Jews. When the Los Angeles couple divorced, he kept the agreement for their daughter but insisted on custody at Christmas, even though for him it's a cultural event, not a religious one. "I'm not celebrating the miracle of Christ's birth. I'm celebrating the American tradition of celebrating Christmas," Johnsrud says.

Broadcast news commentators Steve and Cokie Roberts often talk about their success honoring both his Jewish and her Catholic traditions. They are favorite speakers for the Dovetail Institute, which publishes newsletters and handbooks for parents on multifaith ceremonies and holidays.

But Lutheran pastor and church historian Martin Marty says the trend to "celebrating celebration" trivializes religious teachings, undercutting their power to inspire, guide and comfort lives. A rival group to Dovetail,, calls on parents to pick one religious identity for kids.