*Correction appended.

HOUSTON — On Friday afternoon, Kassandra saw the news on social media. Her immediate reaction was to call her father.

“I told him to be careful out there," she said.

They were talking about what has been called the “family op”, according to The Washington Post: an Immigration and Customs Enforcement plan to conduct a mass roundup of migrant families that have received deportation orders. Federal agents originally planned to target at least 10 cities, including Houston, where Kassandra lives.

The Tribune's reporting for this project is supported by the Pulitzer Center.

“When dad arrived home from work, the four of us sat down, saw the news show, and we made plans," said the 19-year-old immigrant, who asked that her full name not be used.

Her Mexican mom has a resident visa, and Kassandra and her 12-year-old sister are U.S.-born citizens. But her dad is undocumented, originally from El Salvador. Kassandra and her father are the breadwinners in the household. Kassandra is a student and a cashier at a dollar store. Her father works in construction.

“Sitting there, we started making the math, figuring out our savings, how we would pay the bills. We tried to have everything ready, to have the contact information of the immigration lawyer,” Kassandra says.

President Donald Trump said Saturday he was halting the plan for two weeks to give Democratic and Republican lawmakers a chance to close what he called loopholes in the nations' border and asylum processes. But if that doesn't happen, he warned, the deportations will commence.

In Houston, a city of 1.6 million immigrants and about half a million undocumented people, the announcement was a double blow for people like Kassandra. Not only they were worried about the fact that Houston was named as one of the targets, but also they were concerned because the announcement referred to families, not just individuals.

“After listening to that word, the next word that I thought of is separation,” Kassandra recalled.

The memory of last year's zero-tolerance policy along the border, which separated hundreds of migrant children from their parents, remains fresh among immigrant communities. And although Trump said he was postponing this weekend's planned deportation operation, angst remains for many.

“People are afraid. I received so many text messages this weekend,” said Damaris González, a community organizer with United We Dream. “You walk around the streets and people are talking about this. Many of them don’t know their rights, what to do if immigration stops them, how to answer.”

On social media and at community events, immigrant advocates like González have been publicizing what to do if ICE shows up at someone's home or workplace.

Another recommendation, sometimes more difficult to put in place, is to do what Kassandra did: be prepared for the worst-case scenario and have a talk with your family, including planning to have a legal guardian in case both parents are detained.

"Some families are having those conversations,” said Laura Perez-Boston, the Houston campaign manager for labor rights organization Workers Defense Project.

She recommend families know whom to call and which house to go to for help if family members are detained.

“But I've also heard from some parents that would prefer not to have those conversations with those kids because it puts so much fear on them that they can't live a normal childhood," Perez-Boston said. "It is a hard decision that the parents are having to make.”

"She will know what to do"

At a two-story home in northwest Houston, Indira Márquez-Robles’ family tries to go on with life, but it is difficult.

“We are trying to keep living in a normal way, but we have to be very aware of everything,” Márquez-Robles said.

She is a 19-year-old beneficiary of the Deferred Action for Childhood Arrivals program, which gives undocumented immigrants who were brought to the U.S. as minors protections including renewable two-year work permits and a reprieve from deportations. She’s the oldest of seven kids and the only family member, besides her parents, who is undocumented. Her father is currently detained by ICE in Georgia.

She talked about the family's strategies for responding to possible deportations as she stood clad in a red T-shirt with the words "i shouldn't have to show papers to prove i exist" emblazoned on the front.

“My mom is the person in charge. Yesterday, we had conversations about these things," Márquez-Robles said. "Maybe if we should leave the house or not, but we haven’t talked about guardianship. I guess we haven’t had time to talk about the worst-case scenarios."