Wachenheim died at the scene, though her son, Keston, survived the fall when he "bounced off the body," police sources told The New York Post.
DNAinfo interviewed Stephen Dominguez, 18, who witnessed the fall, and his mother:
"I wish I never saw this," he said. "I realized she was coming down but I just didn't believe it."
Dominguez's mother, Adelina Dominguez, 45, raced to the baby to try to help him.
"I saw the baby on the ground and I tried to pick it up, to comfort it, but the police told me not to," she said.
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