Harvard University's Center on the Developing Child has issued a statement calling the US policy of "sudden, forcible separation of children from their parents" a "deeply traumatic" experience for both children and parents. The statement highlights two critical concepts developed from decades of scientific research in child brain development: (1) the importance of a stable and responsive primary caregiver to children's brain development and (2) the negative impacts of persistent stress on learning, behavior, and lifelong physical and mental health.
There are multiple ways to mitigate this potential damage, but the best thing we could do for the children who have been separated from their parents at the border is to reunite them immediately. If children were being fed poison and someone asked, “What’s the best treatment?”, the best answer is not to come up with an antidote. The solution is to stop poisoning them in the first place.