The thousands of children separated from their families in recent weeks are scattered across the country.

I keep thinking about Baby 106. In the 1950s, American psychologist Dr. Harry Harlow used baby rhesus monkeys for groundbreaking research on childhood attachment. One of his subjects, Baby 106, was taken from its mother at birth and placed in a cage. Eventually it was introduced to two “mothers,” that were actually wire cylinders. One had a protruding nipple connected to a bottle of milk. The other, with no nipple, was covered in cloth. The baby monkey initially went to the wire mother and suckled. Then it went, and stayed, with the cloth mother, the one that offered some tactile comfort.

According to Dr. Harlow, babies like 106 formed attachments to their cloth mothers, and could become normal adult monkeys. Those introduced only to the wire mothers never developed attachments, remaining wide-eyed and anxious. JOANN ABRAHAM, “The Cloth Mother and Trauma at the Border,” the Lilith Blog.