Heckel Villa noticed something different as tens of thousands of Catholics made their annual pilgrimage to a suburban Chicago shrine to Mexico’s revered patron saint.

As always, they brought daily concerns about family and health, but the daughter of Mexican immigrants who has worked and worshipped for years at one of the largest shrines to Our Lady of Guadalupe in the U.S. said it was fear and anxiety about President-elect Donald Trump’s approach to immigration that permeated their prayers.

“The spirit was there, but people were actually afraid,” she said Monday during the Feast of Our Lady of Guadalupe. “Their main goal was to pray to make sure that they get some type of answer and trying to make sure our [incoming] president thinks differently, changes his way of thinking, especially with Hispanic people.”

The sentiment was echoed in small parishes and big city cathedrals across the country as Trump’s win and aggressive pledges on immigration changed the dynamic of one of the biggest Catholic holidays, particularly in Latin America.

In response, the United States Conference of Catholic Bishops urged churches to make the holiday Monday a “day of prayer” in solidarity with immigrants and their families and reiterated support for immigrants, regardless of legal status.

Chicago’s Cardinal Blase Cupich brought up the issue at a 5 a.m. Monday Mass at the shrine, as did Catholic leaders at Mass in New York. The University of Notre Dame’s president cited the school’s history of serving immigrants in seeking prayers. In downtown Los Angeles, The Cathedral of Our Lady of the Angels kicked off a day of prayer for immigrant families with a midnight Mass and celebrations continued into Monday evening.

“We really don’t know what the president-elect is going to do,” said Archbishop José H. Gomez of Los Angeles, vice president of the USCCB. He said families are left “wondering how changes to immigration policy might impact them.”

On the campaign trail, Trump called Mexican immigrants rapists and criminals, promised to build a border wall and pledged to deport the estimated 11 million immigrants living in the United States illegally, including children. He has since walked back the number of people that he thinks should be deported, but he hasn’t detailed his immigration plans.

Businesses, local elected leaders and activists have responded by seeking more clarity about potential changes and holding demonstrations, but many people have turned to their faith to find solace, said the Rev. Esequiel Sanchez, the rector at the large shrine in the Chicago suburb of Des Plaines.

He said calling for support and immigration reform on the Feast of Our Lady of Guadalupe was a natural fit.

The feast marks the time when millions make the pilgrimage to a Mexican basilica to honor the virgin believed to have appeared to an Indian peasant on Dec. 12, 1531. Dubbed by several, including Pope Francis, as “the mother of the Americas,” she’s viewed as a protector, among other things. Her iconic image, with hands held in prayer, is found everywhere.

Over 175,000 pilgrims traveled to the Illinois shrine in the days leading up to the official celebration Monday, many of them walking hours to get there, despite a blast of winter weather over the weekend. Worshippers prayed and left flowers by the outdoor shrine featuring a 12-foot-tall replica of the Virgin of Guadalupe.

“It’s absolutely ridiculous to talk about deporting 12 million people quickly,” Sanchez said. “Faith is always an exercise in hope. Part of our creed is people’s minds and hearts can change.”