It was a closed adoption. She never had any contact with the adoptive family, and had no idea what happened to the kid.
Her nephew took one of those DNA tests for a heredity/biology class in college and put that he would allow himself to be contacted by relatives that were found. He was contacted by this cousin, who was adopted out 45+ years ago and was curious about biological relatives. So this person I know has since met her son she put up for adoption.
Pretty crazy.