Margarita Perez held up a Mexican flag as speakers addressed the crowd in Albuquerque, New Mexico.

"Those children that they are incarcerating and separating, they are our future generations. We need to provide for these children," she said. "They will be our future leaders."Two thousand miles away in Boston, a Brazilian mother separated from her 10-year-old son at the border 37 days ago approached the microphone.

"We came to the United States seeking help, and we never imagined that this could happen. So I beg everyone, please release these children, give my son back to me," she said through an interpreter and wept.