Connecticut Shooting Tragedy: The Shooter Of course the question that we have been asking here, what would drive anyone to target children so young, so helpless? Tonight, we're learning more about the connection between the gunman, the school and his family. His relationship with his mother. Here's our chief investigative correspondent, brian ross. Reporter: The connection between adam lanza and sandy hook elementary, goes back to when he was a student. His mother nancy worked as a teacher's aide there. According to adam's aunt. I know that she had issues with school. She wound up home schog him. She battled with the school district, in what capacity, I'm not certain. Reporter: Among those killed on friday, the school psychologist, mary sherlach, who worked with troubled students since 1994, which would include the time that adam was a student there. As a fuller picture of adam lanza began to emerge, including his membership in the high school tech club, former classmates told abc news that he was a smart but socially awkward student. He always carried a briefcase. Reporter: Another former classmate told david muir that adam was a loner. Very timid. Very nervous. If someone talked to him he would be very surprised. Reporter: Adam's parents, peter and nancy, went through an uncontested divorce three years ago, and adam's aunt also said today that nancy had purchased a number of guns because she was living alone. For self-defense, no other reason. Reporter: Police say his mother's high-powered guns were the guns used by adam to kill his mother and those he massacred at the school. A family friend told us that her mother took her sons to a gun range for target practice.