The law firm taking on the case will sue the city of Eloy, Arizona, for $40 million. They said the toddler, Mariee Juarez, was just 18 months old when she and her mother were taken into custody after they fled their native Guatemala and were apprehended at the Texas border.

Stanton Jones is the lead attorney.

"She’s totally heartbroken. She’s devastated, as I think any mother would be to suffer the loss of any child," he said.

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The pair were held at the South Texas Family Residential Center in Dilley, Texas. The new facility opened in 2014 to manage the detention of a surge of Central American migrants. To rush the construction, Immigration and Customs Enforcement used an existing agreement between the city of Eloy and CoreCivic which operates the Eloy Detention Center. It’s an agreement that federal auditors found improper in a report last February. In fact, the report states that ICE's own legal team advised it that the agreement was not advisable. The victim’s attorney argues Eloy was responsible for maintaining safe conditions in Dilley, 900 miles away.

Jones says his law firm is taking on the case pro bono. According to the notice of claim, the 20 year old mother kept asking for intensive medical care for her daughter. The claim says that at one point, a physician’s assistant prescribed Mariee Tylenol and Vick’s Vaporub.

The child died six weeks later, partly of a collapsed lung, when they were in New Jersey awaiting asylum proceedings.

"More so than money, more than any amount of money, she wants to make sure that the people in charge fix this," Jones said.

The firm will also be suing Corecivic and ICE.

An ICE spokeswoman declined to be interviewed because of the pending litigation.

Eloy City Manager Harvey Krauss said the case was turned over to Eloy’s insurance carrier and declined an interview as well citing the pending litigation.