article_snippet: (CNN)Families of children killed at the mass shooting at Sandy Hook Elementary School in Connecticut have filed lawsuits against the estate of the shooter's mother, saying Nancy Lanza was careless and negligent in leaving a Bushmaster AR-15 rifle unsecured in her home.
article_snippet: Adam Lanza, 20, used a Bushmaster AR-15 rifle unsecured in her home to kill 20 first-grade students and six adults in Newtown on December 14, 2012.
article_snippet: Nancy Lanza Nancy Lanza was mentally unstable and used Nancy Lanza mother's Bushmaster to kill his mother before Nancy Lanza went on the rampage at Sandy Hook Elementary School in Connecticut, and then killed Nancy Lanza.
article_snippet: At least eight lawsuits have been filed in Connecticut courts since January on behalf of relatives of 16 people killed in the massacre -- four adults and 12 children.
article_snippet: In December, the parents of nine children killed at the mass shooting at Sandy Hook Elementary School in Connecticut, along with one teacher who survived, filed a separate lawsuit against the businesses behind a Bushmaster AR-15 rifle unsecured in her home.
article_snippet: Report finds missed chances to help Newtown shooter .
article_snippet: A look at Newtown in 2013 .
highlights_snippet: Nancy Lanza son, Adam, used assault rifle to kill 20 first graders and six adults on December 14, 2012 .