In working through the terms of their divorce, the couple spent considerable time talking about how to provide for Adam Lanza's well-being, said Paula Levy, a mediator who worked with the couple.
During their meetings, the couple mentioned that Adam Lanza had been diagnosed with Asperger's syndrome, an autism-like disorder, Levy said. But the Lanzas were in complete agreement on how to address Adam's needs and said little about the details of his condition, Levy said.
"The only two things I remember them saying is that she really didn't like to leave him alone and I know they went out of their way to accommodate him," said Levy, who recalled Nancy and Peter Lanza as very respectful of each other and equally concerned about their son's needs.
"They worked together about it," Levy said. "The mom, Nancy, pretty much said she was going to take care of him (Adam) and be there as much as he needed her, even long-term."
While she would not disclose details of their discussions, Levy wanted to make clear that the Lanzas were loving parents who wanted the best for their son.
"These people are soft-spoken, gentle, both of them saying, 'What can we do to help him?'" Levy said.
The lawyer who represented Nancy Lanza in the divorce also spoke positively of her, calling her courteous and polite.
"She was an intelligent woman who we were pleased to represent," said the firm of Piazza, Simmons & Grant in Stamford.
Adam Lanza shot his mother in the head with a rifle Friday, then headed to Sandy Hook Elementary School armed with her high-power rifle, two handguns and enough ammunition to kill nearly every child in the building, authorities said. He killed 20 students and six adults before police arrived and he shot himself.
The Lanzas married in June 1981 in Kingston, N.H. Nancy Lanza filed for divorce in 2009, by then living with her son in the home where she was found dead in her pajamas, on her bed.
The documents suggest little argument. The couple agreed to split up their jewelry, clothes and family photos. Adam would live with his mother, the couple agreed, and they agreed to talk about the important decisions.
If it turned out they couldn't agree on something related to Adam's upbringing, Nancy Lanza "shall make the final decision," according to the Sept. 24, 2009, settlement approved by Judge Stanley Novak.
There is nothing in the divorce court file that discusses the relationship's underlying problems. The file simply says the marriage "has broken down irretrievably and there is no possibility of getting back together."
Nancy Lanza, received $289,800 in alimony this year. It was to continue until December 2023, with slight increases each year for cost of living.
As part of the divorce, both Nancy and Peter Lanza were ordered to attend a parenting education program, standard practice in Connecticut. The provider, Family Centers Inc., certified that both completed the required sessions.
Authorities pored over computer, cellphone and credit card records trying to piece together the Lanza family's days leading up to the shooting. Peter Lanza, in a statement this weekend, said that like everyone else, he could not comprehend what had unfolded.
"We too are asking why," he said. "We have cooperated fully with law enforcement and will continue to do so. Like so many of you, we are saddened, but struggling to make sense of what has transpired."
Asperger's is a mild form of autism often characterized by social awkwardness. While people with the disorder can become frustrated more easily, there is no evidence of a link between Asperger's and violent behavior, experts say.
AP National Writer Adam Geller reported from Southbury, Conn.
ATF says Conn. gunman not at ranges recently
Federal agents say the gunman in the Connecticut school shooting fired guns at shooting ranges over the past several years, but there's no evidence he did so recently as practice for the rampage.
Debora Seifert, a spokeswoman for Bureau of Alcohol, Tobacco, Firearms and Explosives, says Adam Lanza and his mother each fired at shooting ranges. They also visited ranges together.
But Seifert tells the AP that ATF investigators have no indication now "that the shooter engaged in shooting activities in the past six months."
One of the major unanswered questions has been whether Lanza trained in advance for Friday's attack that killed 20 children and six adults inside the Sandy Hook Elementary School in Newtown, Conn. Lanza also killed his mother at home and himself.