Two sets of siblings -- a pair of sisters and a pair of brothers -- who are gaining notoriety on tour as the Vespers will be performing at the Hamilton on Sunday evening.

"The Vespers is an easy [band] name to say," noted Phoebe Cryar, who, along with her sister, Callie, make flawless harmonies as lead vocalists while also playing acoustic guitar, banjo and ukulele. "It's a term for evening prayers -- everything we do is praise, and at the same time, we're entertaining you."

Together for just about four years, the Vespers have a folk-Americana sound that is akin to bluegrass inflections with a touch of roots sounds drawn from spiritual themes. But that only partially defines a style also characterized by rock, pop and blueslike rhythms.

"We all grew up [in Nashville, Tenn.] listening to a little bit of everything, but roots music didn't come in until more recently," said Bruno Jones, who, together with his brother, Taylor, fill out the foursome's sound on a variety of instruments that include drums, upright bass, guitar and mandolin. "Folk and roots music tend to draw from spiritual themes. We don't run away from our faith when writing, because that's where our hearts are planted."

The Vespers
» Where: The Hamilton, 600 14th St. NW
» When: 6:30 p.m. doors, 7:30 p.m. show Sunday
» Info: $17 in advance, $19 day of; 202-787-1000;

All four of the group's members share in the writing, with Phoebe Cryar composing the bulk of the music, or as she quips, "I begin more of the songs and get one of the others to finish for me." And one of the others almost always does, providing the group with an additional cache of lively and animated pop songs.

Additionally, the music from their two albums, "Tell Your Mama" and "The Fourth Wall," have the energy of a live show, because the band polishes them on the road. The decision to tour shortly after they formed the Vespers was a good move in that they learned what their band was all about in front of live audiences.

"We'll play a long set [and] will probably have an even mixture of songs from our two albums, new songs and a few covers," Phoebe Cryar explained. "We'll talk between songs because we all have vibrant personalities."

On a serious note, she adds, "I'd like audiences to go away with joy and a sense of peace [over] things they never thought about before."