Adam Lanza is shown in 2005 in a photo provided by a neighbor in Newtown, Conn. (Barbara Frey, AP )
STAMFORD, Conn. — When the parents of Adam Lanza divorced, the settlement left Nancy Lanza with $24,150 a month in alimony payments and able to live a comfortable life and care for her troubled son.
Nancy Lanza, 52, was her son's first victim Friday, shot to death in the spacious home they shared, authorities said. Adam, 20, then took his mother's car to Sandy Hook Elementary School, where he shot his way into the building and opened fire, killing 20 children and six adults before turning a gun on himself.
New details emerged Monday about how Adam Lanza's family and the staff at his high school kept a watchful eye over the reserved boy, who seemed to spend much of his time in solitude after finishing high school.
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Friends of the family said he suffered from Asperger's syndrome, a form of autism. As early as age 10, Adam Lanza was taking medication, according to his former baby sitter, Ryan Kraft, now an aerospace engineer in Hermosa Beach.
"I know there was something administered. I'm not sure what," he said. There were never any signs that Lanza was dangerous, he said. "There were no red flags that would say something like this would happen."
Nancy Lanza cautioned Kraft to never let him out of his sight, even briefly. "The instructions were to always supervise him visually," he said.
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That echoed recollections from others who said Nancy Lanza was a constant presence in her son's life. "She truly cared for both of her sons deeply," said Amanda d'Ambrose, 23, whose brother befriended Adam Lanza in high school. "I just want the world to know what a beautiful soul that she is."
John Wlasuk, who played Babe Ruth baseball with Lanza as a youth, said the boy's mother was "always at the games, always really involved with her kids."
Wlasuk said he sometimes went to the Lanza house with his father, a plumber, who told him of the room in the basement where Lanza spent a lot of time playing video games. As Wlasuk's father described it, the room had posters of military weaponry, and Lanza would be playing violent video games such as "Call of Duty."
"I wouldn't say it was a shrine to the military or anything, a couple of posters with a bed and a desk and a computer," he said.
Richard Novia, who formerly advised the Newtown High School tech club that was one of Lanza's few social outlets, said Lanza had been placed in a special program for students who were considered at risk of being bullied — though he had no recollection of Lanza being harassed.
Novia said he was told that Lanza had a medical condition that hindered his ability to feel pain, so that if he cut himself or stubbed his toe, he might not even know he was hurt and could continue to harm himself.
When Lanza was in elementary school, his mother fretted about his schooling.
"She was concerned mainly that Adam wasn't fitting in well in his classroom," said Wendy Wipprecht, whose son had also been diagnosed with a form of autism. She said Nancy Lanza considered moving her son to a private Catholic school, or home schooling him, but did not join sessions of any of the local autism parents' support groups that Wipprecht attended.
"She may have decided that there wasn't a support group that would fit," Wipprecht said. "Who knows. She may have been overwhelmed."
There is no mention of Adam Lanza's emotional troubles or any domestic strife in his parents' divorce papers. Last week, Ryan Lanza told investigators that the divorce could have had an effect on his younger brother.
Peter and Nancy Lanza married in 1981 in New Hampshire. She sued her husband for divorce in 2008, citing irreconcilable differences.
In their 2009 settlement, Nancy and Peter Lanza agreed to joint custody of Adam, then 17, who would live with his mother but have regular visits from his father. In addition to the alimony, Peter Lanza would cover the children's medical insurance.
Court records show that Nancy Lanza was due to receive $289,800 in alimony in 2012, or $24,150 each month. Peter Lanza, an executive at General Electric who was earning an annual salary of about $445,000 in 2009, also would pay for both their sons' college and graduate school educations and for a car for Adam.
The street where Nancy Lanza and her son lived was reopened by police Monday. The borders of the grassy, tree-lined hill it sits on are still cordoned off with yellow police tape.
Bengali and Hennessy-Fiske reported from Newtown, Conn., and Murphy from Seattle.