If you’re a mom or a dad with two daughters, sisters who are one year apart, you might suspect that they would grow up as best friends, sticking together through thick and thin.

It is possible that Craig and Robbin Sarine thought their daughters, Sarah and Andrea, might end up getting married in the same year and even planned for that prospect. But what if those two girls decided to get married on the very same day?

This Saturday, sisters Sarah and Andrea Sarine will marry their fiancés in a double wedding ceremony at UTC’s Patten Chapel. Their grooms are best friends from Sparta, Tn. The boys grew up together after their families met at church.

Andrea and her beau, John Kay, met in 2003 as freshmen at Union University in Jackson, Tn. The two set Sarah up with John’s best friend, Jonathan Johnson, over the 2006 Fourth of July weekend. Both daughters were engaged within five days of each other in January.

Then they started wrestling with wedding dates. Mrs. Sarine wanted “two months!” between the weddings to give friends and family a break. July was perfect for one sister, but May was too soon for the other and June was occupied by a nonrefundable trip to Germany. They even toyed with getting married the same weekend, one on Friday and one on Saturday, but budget realities pulled in the reins.

Finally, Sarah said, Jonathan suggested the inevitable as a joke: that they get married together. When the idea started getting serious, Andrea owned up to her wish to have her own day. After a long discussion with her fiancé, Andrea realized that as long as she was John’s princess that day, the rest was superfluous.

They were all in: the girls would get married on the same day, at the same church, with separate vows to separate men in a double wedding ceremony, and then ride off to the same party.

“It’s been crazy ever since, but it’s cool,” said Andrea.

Mrs. Sarine said she immediately declared her neutrality, leaving it completely up to the sisters to choose colors, music, cake and the rest. “I did not want to be caught in the middle…It’s a lot of moving parts,” she said.

What about the grooms’ families? “They just bought right into it,” said Mrs. Sarine. “They were so excited to do the rehearsal dinner and the mother of the groom thing together.”

There was absolutely next to nothing on the Internet or anywhere else about double weddings, though the occasional department store clerk mentioned a cousin’s double wedding in the ‘60s. But instead of becoming discouraged, the family realized they could do whatever they wanted.

Both sisters agreed that Sarah is the instigator, spouting ideas. Andrea tweaks them to make them actually work. They limit their wedding conversation to 15 minutes at a time so Andrea, who admits she’s not the laid back one, won’t get overwhelmed.

Dr. Mike Chapman of City Church will marry the two couples. The brides chose different colors, and the bridesmaid procession will alternate blue and brown. Sarah has her own ring bearer, flower girl and music. Then Andrea has her own ring bearer, flower girl and music. Sarah will enter the church first, so Andrea and John will recess first.

Both couples will take a horse-drawn carriage to the guys’ cars and then will ride up separately to the reception at Rock City Pavilion on Lookout Mountain. They’ll each have their own favorite cake at the reception, one will throw the bouquet and one will throw the garter. Andrea will cut in on Sarah’s father-daughter dance.

Mr. Sarine chose Mark Harris’s song “Find Your Wings,” which says, “So let my love give you roots / And help you find your wings.”

“It’s really hard for him to give away two at once,” said Mrs. Sarine, speaking for both of them. She said she keeps him busy so he won’t have time to think about it, but she said, “I think Sunday will be hard for us…” then added, “But it’s a new season.”

After the wedding, Jonathan and Sarah Johnson will return to Winchester, Va., where he will complete a master’s in reading and she will continue physical therapy school. John and Andrea Kay will stay in Chattanooga, where he will teach history and she will pursue nursing.