In the 1990s, Kerwin worked at the University of Wisconsin-Madison’s Harlow Center for Biological Psychology and cared for 97 rhesus monkeys, the same species she cares for today.
The center was named after Harry Harlow, a scientist who used methods of isolation and maternal deprivation on infant monkeys to show the impact of contact and comfort on primate development in the 1960s and 1970s.