(CNN) For weeks, money has been pouring into RAICES to help reunite families separated at the US-Mexico border.

Today, the Texas nonprofit announced what it's going to do with the funds: It will march to Capitol Hill with a $20 million check to demand that immigrant mothers be released from detention centers.

"Bonds often cost between $5 -10,000 so our $20m can pay approximately 2,500 in one go," the group said in a statement.

To be sure, the move is a symbolic gesture. It's meant to highlight how the government has been slow to meet its Tuesday deadline to reunite children separated from parents who were caught crossing illegally at the border.

About 2,500 kids have been separated from their parents, RAICES estimates. Roughly half of the children under 5 years old will be back with their moms and dads by the deadline, but the Trump administration is still not sure when the rest will be reunified

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