In the corner of a small community center in Langley Park, Md., two women stuffed padding around Maria Lopez’s stomach so she would look like a pregnant Virgin Mary, then adjusted the light blue dress with gold trim. As a finishing touch, they centered her traditional Middle Eastern headdress to make her appear as though she stepped out of the biblical story of Jesus’s birth.

Wearing brown robes and holding a large walking cane, Jose Ventura, playing Joseph, leaned over to pose for a quick photo with his Mary before the time came to march through the streets. A crowd of about 200 Latino Catholics had lined up outside to embark on another night of Las Posadas this week, a symbolic reenactment of Mary’s and Joseph’s search for shelter and a long-standing Advent tradition.

As they caroled through Langley Park on Monday night, residents in apartment buildings emerged onto balconies to watch them reenact the story of the trek to Bethlehem. They blocked the eight-lane New Hampshire Avenue as some of the children carried candle-lit lanterns to illuminate the way.

The Latino tradition of Las Posadas is especially popular for St. Camillus, whose 4,500 attendees include mostly immigrants from Guatemala and El Salvador. Many of the parishioners who have made their home in Langley Park — a key gateway for Hispanics immigrating to the region — relate closely to the story of Mary and Joseph, who left their own home to escape to Egypt.

Las Posadas, which means shelter or lodging in Spanish, is a tradition that originated in Mexico but is celebrated by all kinds of Latino Catholics, said Peter Casarella, a theology professor at the University of Notre Dame.

Linda Lopez, 7, of Langley Park, holds a candle lantern during the procession. (Sarah L. Voisin/The Washington Post)

“It’s an essential part of the Advent season, the sense of expectation of the coming of Christ. It’s a way of inserting yourself back into the Bible,” Casarella said. “It’s not just a story from far away. Making it real, and making it something that’s close to home, fits in closely with Hispanic/Latino theology.”

Although other parishes in the D.C. area host Las Posadas, a spokeswoman for the Archdiocese of Washington said many are encouraged to join the celebration at St. Camillus, one of the archdiocese’s larger and most diverse parishes.

Every night for nine days ending on Christmas Eve, the crowd of parishioners hits the streets, following Mary and Joseph as they pretend to seek shelter. Each night, they visit two homes. In the first, the crowd sings songs and says prayers in Spanish, and in the second home, they use the Guatemalan language known as Mam.

In his brown Franciscan habit, Father Erick Lopez, the parish priest, led the way one night this week, announcing the next Christmas carol with his megaphone and urging the crowd to “Make a joyful noise!”

“We yell a lot,” he said jokingly as he fixed a child’s fur hat.

As they marched through the area’s many apartment complexes, the group swelled with carolers who joined along the way.

When the carolers finally arrived at the apartment of a parishioner, they sang at the door of the family members living inside who pretended to be the innkeepers. According to biblical tradition, before Jesus’s birth, Joseph and Mary traveled to Bethlehem and were denied shelter from inns, which were full.

The group packed into a small living room at the first home of the evening to pray. Yenifer Baca, 10, played Mary and Carlos Morales, 13, played Joseph. (Sarah L. Voisin/The Washington Post)

As they sang a traditional song back and forth with the family inside the home, the crowd began by asking for shelter from the homeowners. The homeowners responded by singing that they could not take Mary and Joseph in. Taking turns singing on either side of the door, the homeowners finally relented, welcoming Mary, Joseph and the pilgrims to enter their home.

A party ensued, at least for the ones who could squeeze into the apartment. The crowd belted out more Christmas carols such as “Feliz Navidad,” reciting the Lord’s Prayer and praying the rosary as they passed foam cups of hot chocolate to each other.

Under her red Santa hat, Sandra Robles’s eyes glistened as she smiled widely and said she has participated in Las Posadas nearly every night for the past six years.

“People say this neighborhood is terrible, but I love the people here,” said Robles, who lives about two miles south near Green Meadows.

As she began to lose her voice, Robles said she should try to keep her mouth shut so she could sing again on Christmas Eve, the final night of Posadas where the tradition ends with Mass. But she kept caroling anyway, singing the lines “Gloria in excelsis Deo.”

“This is bringing part of your roots to the U.S.,” said Robles, who is from El Salvador. “It makes people feel at home here.”

At the second home that night, the carolers squeezed into a duplex, wrapping around the corner and up the stairs. “Make us a place of peace and joy, like a family,” they prayed before reading Jesus’s birth story from the Gospel of Luke.

Leonel Lopez, a 27-year-old construction worker from Langley Park, said he has been helping to coordinate Posadas for the past seven years. After his parents both died, he moved to the United States at 17, and Posadas helps him remember his home in Guatemala.

“I cannot forget my traditions,” he said as he pulled out the sheet of paper to show all the names and home addresses of people who agreed to host Posadas every night. “I love it, really I do.”

David Montgomery contributed to this report.