As the nation marks the ninth anniversary of 9/11, a new study finds that the youngest victims, children under five years old who witnessed the attacks, suffered trauma and require treatment. In addition, their ability to heal relies heavily on how the adults around them have responded.

The study, led by Tovah P. Klein, director of the Barnard Toddler Center and a psychology professor and Ellen R. DeVoe of Boston University, serves as “evidence that we continue to learn lessons from 9/11 that are applicable to the ongoing wars worldwide, the Haiti earthquake, the Pakistani floods, and other disasters children witness”, Professor Klein said. “So little is written on preschoolers and trauma, particularly related to 9/11. This research helps us understand and treat young children who are most often overlooked following a traumatic event. Since the 9/11 attacks were unprecedented acts of terrorism, the disaster provided an opportunity to understand the responses of young children to a traumatic event of this proportion.”

Klein’s article “Young Children in the Aftermath of the World Trade Center Attacks” (also with William Bannon, Jr. of Mount Sinai School of Medicine and Claudia Miranda-Julian of Tufts) will soon be published in Psychological Trauma: Theory, Research, Practice, and Policy, an American Psychological Association journal. Klein and her team interviewed 180 children who were under age five and living near the World Trade Center on 9/11.

The findings also highlight the importance of the family environment for the recovery of young children. “Because young children are so immersed in the family, the stress and negative impact of the attacks on the parents also affected the children,” Klein said. The researchers found that children’s trauma symptoms were related to direct exposure to the disaster, previous trauma, negative changes in parenting and increased tension between parents.

Klein studies children’s social development, the influence of parents on children’s development, and the experience of parenting young children. She also focuses on the impact of trauma on young children and their families. Klein serves as an advisor to “Sesame Street” and HBO for children’s documentaries, and on the advisory boards of Room to Grow, NYC Voices of Childhood, and the Rwanda Education Assistance Project.

Founded in 1889, Barnard College was the only college in New York City, and one of the few in the nation, where women could receive the same rigorous and challenging education available to men. Today, Barnard is among the strongest liberal arts colleges in the country, and the most sought-after women’s college.