He landed 30 feet below the bridge on concrete, News 12 Westchester reported.
Ferreira Cavallo immediately pulled over, grabbed as much first-aid supplies as she could, and jumped off the same overpass to help him.
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"I wasn't thinking too much," Ferreira Cavallo told USA Today. "I just knew, when I looked down and saw him ... he looked dead. I couldn't see anything other than blood. I thought to myself, 'He needs help. I need to help him.'"
Ferreira Cavallo and another woman who was dressed in a military uniform helped the boy, who appeared to be a young teen. He was unresponsive, but he did open his eyes. They were able to put him in a neck brace and splint and check his airway.
The boy was taken to a local hospital for broken bones and other injures, but his condition was not released, News 12 Westchester reported.
It didn’t sink in for Ferreira Cavallo until the next day.
"I went to work and worked to 11 p.m.," she told USA Today. "I didn't realize what was going on until yesterday. That's when it hit me. I didn't realize how high it was. It seemed doable. It didn't seem that high. I thought I jumped over a brick wall, or a cement barrier. It was so fast. It was more like tunnel vision. I saw the boy and I needed to get to him. I didn't see anything else."
The teen is between 12 and 13 years old and is a student at a school for vulnerable children that is located less than 2 miles away from where he jumped, News 12 Westchester reported.