For identical twins Darlene and Diane Nettemeier of Aviston, it was love at first sight times two.

Their perfect matches? Identical twins Craig and Mark Sanders of Houston.

On Nov. 13, Darlene, Diane, Mark and Craig will mark their 10-year anniversary. (The families also will be featured in an upcoming TLC special that will profile three sets of twins who married twins. The air date hasn't been set).

The Nettemeier sisters and Sanders brothers met at the annual twins convention in Twinsburg, Ohio, in 1998. They stayed in touch via phone, e-mail and double dates, including trips to Las Vegas and Florida. Their double-wedding was the first in Aviston, in Clinton County about 45 minutes east of St. Louis. As they left the church, with a nod to the TV commercials that featured twins, they threw Doublemint gum instead of rice.

The families now live in Missouri City, a Houston suburb, in side-by-side homes with a shared backyard and phone numbers that are one digit apart.

The biggest joy, challenge and high point of the last 10 years? "The birth of our children," says Diane, 39. "That was all three — the biggest joy, challenge and high point."

Diane and Craig, 45, have identical twin sons Brady and Colby, 8, and their brother Holden, 4. Darlene and Mark have two daughters, Reagan, 7, and Landry, 6.

The families get to St. Louis at least once a year. This summer Mark, who's a letter carrier, and Darlene and the girls went up in the Gateway Arch; Diane and Craig and the boys went to Cahokia Mounds (Craig teaches American history in high school), and tried to go to Grant's Farm but wound up at Ted Drewes instead.

The sisters were back in Aviston in February, too, when their father had quadruple bypass surgery.

Much of the families' time back in St. Louis is spent with Diane and Darlene's parents, who have retired but still have the family farm, and their sister, who lives in Edwardsville.

"The boys love the farm and the animals and the tractor rides," Craig says.

"I still haven't seen a Cardinals game in the new Busch Stadium though," Diane adds. "I'll always be a Cardinals fan."

They subscribe to the weekly Breese Journal newspaper, which they receive in the mail. Darlene says it's great to keep in touch with what's going on at home, and she and Diane know so many of the people in the stories in the paper.

The sisters, who both worked as legal secretaries in downtown St. Louis at the Greensfelder law firm, now work for two big law firms in Houston that are about a block apart.

"We meet for lunch every day and carpool," Darlene says.

When Diane and Darlene drop Holden off at day care, some of the other children still do double-takes and are a bit confused. "They think Holden has two mommies."

Diane explains her twin bond: "You always have someone who understands what you're going through. I feel very lucky."

At home, the twin couples share responsibility for the kids.

"We have built-in baby-sitters," Mark says, explaining the side-by-side houses. "It's a nice thing. We can have a date night, and the next week we can watch the kids so Craig and Diane can have a date night.

"We face the same challenges every family struggles with — raising kids, finances," he adds. "Maybe we're a little different, but when you scratch the surface, we're just two normal families."

Normal families maybe, but identical twins marrying identical twins are rare, with maybe 250 "quarternary marriages" worldwide, Craig and Diane Sanders wrote on a blog post on their twinstuff.com website.

Twins expert Nancy Segal, a professor of psychology at California State University at Fullerton and author of two books on twins, says she's not sure there is an accurate number of twins who marry twins, but she thinks the number may be on the rise, partly because the incidence of twins is increasing and partly because of the special bond between twins.

"Some twins, mostly identical, know that other identical twins understand the importance of the twin bond," she said, "and it is possible to preserve that bond on a daily basis when twins marry twins."

What's planned for Diane and Craig's and Darlene and Mark's 10-year anniversary? After all, the brothers, then owners of a website design business, each proposed via a special webpage invitation for Darlene and Diane. The sisters clicked yes.

Their engagement rings were two identical diamond rings, the late Post-Dispatch columnist Greg Freeman wrote 10 years ago.

"We need to do something special," Mark says. "We haven't quite figured out what yet though."