Adam Lanza killed his mother and then 20 first-graders and six adults at Sandy Hook Elementary School in Newtown, Conn., on Dec. 14, 2012.
Adam Lanza's father remains "broken" and family members are "shaken to the core" and stigmatized a year after the Sandy Hook Elementary School massacre, his aunt has told a British newspaper.
"Peter has only spoken about it to a very, very small number of people, including my husband, Michael, his brother, as they are very close," Lanza's sister-in-law, Marsha, told the Daily Mail from her home in Crystal Lake, Ill. "'Peter is a changed man. He's broken. How can you ever begin to try and deal with that? It's just impossible."
Dec. 14 marks the first anniversary of Adam Lanza's spree. He first killed his mother, Nancy, in her bed, and then slaughtered 20 first-graders and six educators at the school in Newtown, Conn., before taking his own life.
Investigators said the antisocial 20-year-old was obsessed with violent video games and mass murders. He was diagnosed with Asperger's syndrome, an autism-spectrum disorder not associated with violence.
Peter and Nancy Lanza divorced in 2001, but he had regular contact with Adam until their relationship deteriorated. He last spoke with his son in 2010.
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The family is still at a loss to explain what motivated the blood bath, and has not had a "big family meeting or anything" to discuss it, Marsha Lanza said.
"Was there something more we could have done? Did we miss the signs?" she said. 'I went over old Facebook messages that Nancy sent me at the time and nothing seemed to indicate this was coming. We're still struggling to understand it ourselves.'
She also told how her children have been taunted and she has been shamed in public because of their last name.
"It happens everywhere - the bank, restaurants, gas stations," she said. "You see them see the name ... and then you know what they're thinking. I know what's going through their mind."
Peter Lanza, who recently returned to work, did want to add anything beyond thestatement he issued after the shooting, a family spokesman told the paper.