Kelsey Bozarth and her family always celebrate Christmas Eve with a special song.

They cue up Bing Crosby's "Mele Kalikimaka," often called "the Hawaiian Christmas Song," and sing along. Sometimes they even dance.

It's doubtful this endearing ritual, begun decades ago by Bozarth's grandfather, had ever been the subject of a scholarly discussion in a university classroom. Until this year.

"I told my professor, 'I have this family tradition and I'm really passionate about it,' " explains Bozarth, 21, a Rowan University senior from Burlington County.

Dianne Ashton, who teaches religion studies at Rowan, liked Bozarth's idea to use "Mele Kalikimaka" as a jumping-off point for a senior writing project.

After all, Hanukkah rituals in Ashton's family have inspired her to write a book, Hanukkah in America, which she expects to complete next year.

"Like many students in my Holiday Celebrations in American Culture class, Kelsey chose a topic that related to helping her understand her own family," Ashton says.

"The only way to do these topics successfully is to be able to find scholarship and do the original research," adds the Cherry Hill resident, who has taught at Rowan for 22 years.

A bit of Googling won't cut it. Ashton expects her students "to go to primary sources, and to interview people" because a Christmas song can be more than a merry tune.

"Not only are ideas expressed in music, emotions are expressed," she says. "Music makes us feel different."

In researching what turned out to be a 21-page paper, Bozarth looked into music's physiological effects.

"When people sing songs together, our brains produce chemicals that make you feel togetherness," she says. "And that's what Christmas is basically all about."

"Mele Kalikimaka" - the title is an island version of "Merry Christmas" - was written in 1949. It has been a Christmas Eve highlight in Bozarth's family for as long as she can remember.

The festivities take place in Burlington Township, where she grew up and lives.

"We would always go to the children's Christmas Eve service at the Presbyterian church and then to my maternal grandparents', Edward and Clara Viereck," she recalls.

Her grandfather, a music lover, would start the record - later, a CD. That was the signal to his 11 grandchildren, their cousins, aunts and uncles, and anyone else to run to the living room.

"We don't really have any specific moves, but we would try to do the hula, and just dance with our family. Poppy would get out his video recorder and tape us," Bozarth says.

"When I was a teenager, I was kind of embarrassed," the 2008 Burlington Township High School graduate acknowledges. "But I still loved it."

She also loved her grandfather, nicknamed "the Big Kahuna," who died in 2009 at 74.

"He was basically the center of our family," Bozarth says.

"We think the reason why he loved the song so much was because when he married my grandmother, he said he would take her to Hawaii on their 25th wedding anniversary.

But they weren't able to go because they didn't have enough money."

At a party for their 50th anniversary, in 2004, he put on "Mele Kalikimaka," and the family performed.

"And when we were done," Bozarth says, "he handed her the tickets" to Hawaii.

This Christmas Eve, as always, Bozarth and the rest of the clan will gather at Nanny's house.

"My grandfather was her everything, and the loss has been hard on her. It's important to her that we keep his memory alive."

So when the time is right, Bozarth will cue up "Mele Kalikimaka." And she'll dance.