BOSTON (AP) — Brazilian immigrant Sirley Silveira Paixao sobbed openly onstage in Boston as she described being separated from her 10-year-old son at an immigration rally on Saturday.

Silveira Paixao was one of many speakers at the Rally Against Family Separation, one of two protests in the city attended by thousands. They decried the Trump administration's policy of separating families who enter the country illegally.

Democratic Sen. Elizabeth Warren, at a rally at city hall, said the Immigration and Customs Enforcement agency needs to be replaced with "something that reflects our morality."

She said Republican President Donald Trump thinks the only way to have immigration rules is "to rip children from their families." Congressman Joe Kennedy III and Sen. Edward Markey, both Democrats, also attended the rally.

Silveira Paixao, 30, said she surrendered herself and her son Diego for asylum at the border of the U.S. and Mexico in May. They were detained at a customs and border patrol facility.

When Diego became ill with a 103-degree fever, the boy and his mother were taken to a hospital, where Silveira Paixao said she was told he would need continued observation. They've been separated since May 24.

"It was just the worst moment of my life," Silveira Paixao said. "I had impression I would never see him again."

After pleading guilty in federal court to unlawful entry, Silveira Paixao was released to an acquaintance in Boston where she waits to hear more about her asylum case. She learned her son was being held at a facility in Chicago, and now talks to him on Sundays and Wednesdays for 10 minutes at a time.

"Please," Silveira Paixao said, "give my son back to me."

Neela Jayaraman, 39, said as an Indian immigrant and social worker, President Donald Trump's family separation and detention policies devastate her.

"As a mother, I can't look at those cages," she said, referring to the structures where some children have been detained. Cradling her 8-month-old baby Akira, Jayaraman said she has hope that things will change because of the large number people opposed to separating families.

Sara Ramirez, a recent addition to the show "Madam Secretary" and a former cast member of "Grey's Anatomy," called for donations to groups advocating for changes in immigration policy.