Demonstrators in Washington protest the Trump administration’s decision to wind down the Deferred Action for Childhood Arrivals (DACA) program. (Andrew Harrer/Bloomberg News)

Among the many dramas of the Trump presidency has been whether he would fulfill his campaign promise to dismantle the DACA program. Months of speculation and mounting anxiety among immigrants and their advocates culminated Tuesday, when Attorney General Jeff Sessions announced that the Trump administration would rescind DACA protections in six months’ time.

The program, Deferred Action for Childhood Arrivals, provided temporary relief from deportation and the right to work for unauthorized immigrants who had been brought to the United States as children. To date, some 800,000 of these “dreamers” have successfully applied for the deferred action.

The press has focused its attention on the plight of these young people — some now adults in their 30s — many of whom have no memories of living elsewhere. What has been ignored is the predicament of the DACA recipients’ children, most of whom are U.S. citizens by birth.

When DACA was announced in 2012, those eligible for the program were parents to an estimated 200,000 children. This constitutes a subset of the estimated 5 million children in the United States who have at least one unauthorized immigrant parent.

How does DACA protection for parents affect the lives of their children? Our Stanford Immigration Policy Lab study, recently published in Science, produced this striking finding: when mothers are eligible for DACA protection, their kids’ mental health improves dramatically.

We used data from Oregon’s Emergency Medicaid program to identify mothers who gave birth to children born between 2003 and 2015. The program provides coverage for labor and delivery, and most of the program’s participants are unauthorized immigrants. Since the children of these mothers are U.S. citizens by birth, they are eligible for the broader Medicaid program, and we could thereby track their mental health outcomes over time.

To be eligible for DACA, people had to be born after June 15, 1981. This arbitrary date creates a sort of experiment, since DACA recipients born just after this cut-off date should be similar to those born just before, who were not eligible for DACA. The same should be true for their children. So by comparing these children after DACA was implemented, we could determine how DACA protection for mothers affected their children.

Our study focused on diagnoses of adjustment and anxiety disorders, mental illnesses known to be provoked by external stress and that can produce lifetime challenges for children. Childhood mental illness also accounts for the highest share of the nation’s pediatric health care spending.

Here is what we found: children with mothers born either before or after the DACA age cutoff were diagnosed with these disorders at roughly the same rate before DACA was implemented:

But after DACA was introduced in 2012, a gulf immediately opened between the two groups:

Compared to children of mothers who were not eligible for DACA, children with DACA-eligible mothers had a far lower rate of mental health diagnoses: 3.3 percent versus 7.8 percent.

Our results have troubling implications for the end of the DACA program. It is rare to find a social problem as complex as mental illness that can be significantly improved with a single law. Without it, the children of dreamers could be harmed by the looming threat of being separated from their parents.

But there remains an opportunity for Congress. If Congress takes steps to provide legal protection to dreamers, their children will likely benefit too.

David D. Laitin is the Watkins Professor of Political Science at Stanford University. He is the faculty co-director of the Stanford Immigration Policy Lab (IPL), and co-author of “Why Muslim Integration Fails in Christian-Heritage societies”.

Linna Martén is a post-doctoral scholar at the Stanford Immigration Policy Lab.

Jens Hainmueller is a professor of political science and business at Stanford University. He is the faculty co-director of the Stanford Immigration Policy Lab (IPL).