I represent amicus American Professional Society on the Abuse of Children in the U.S. Courts of Appeals for the Second and Ninth Circuits in the DACA litigation.
APSAC argues that rescinding DACA will harm the tens of thousands of U.S. citizen children of DACA recipients. Given DACA rescission, then deportation of their parents, these children will have to choose between remaining in the country of their birth and birthright--if that's even possible for them--or returning with their parents to a country they do not know. If DACA recipients are detained and then deported, their children may be taken by CPS and adopted out, especially if the United States' relationship with the parents' native country is insufficient to support the return of the child.
Even the threat of deportation can cause children to suffer traumatic stress, a medical condition that can affect cognition, self-regulation, and ability to participate in school in the short term, and has been durably linked to seven of the ten leading causes of morbidity and mortality in the longer term.
You can read the Second Circuit brief here and the Ninth Circuit brief here. The Ninth Circuit argument is in Pasadena on May 15 and will be broadcast on CSPAN.