NEWTOWN, Connecticut (CNN) -

The mother of the man identified by authorities as the gunman behind an elementary school massacre liked to play parlor games in a ladylike setting with neighbors, discussing their landscaping and backyard gardens in this charming exurb some 60 miles from New York City.

Nancy Lanza was a personable neighbor who lived on a block of spacious houses on a crest overlooking gentle hills, acquaintances said.

She and her family moved to the Sandy Hook neighborhood about 1998, raising two sons with husband Peter until the couple separated a few years ago.

"It was just a nice, normal family," neighbor Rhonda Cullen said Saturday, recalling a recurring neighborhood ladies night over the Bunco dice game.

"We used to joke with her that she'd do all this landscaping that no one could see because it all was in the back, and because her house was so set back," added Cullen.

At odds with this image of New England gentility was how the Lanza household possessed a cache of weapons -- including an assault-style rifle and two handguns -- in a community prized for its stillness.

Those weapons were found with Nancy Lanza's younger son, Adam, 20 -- whom three law enforcement officials said was the gunman in Friday's mass shooting at Sandy Hook Elementary School.

After gunfire at the school killed 20 children and six adults -- the second deadliest school shooting in U.S. history -- the shooter killed himself, officials said.

Before Friday's rampage, authorities said, Adam Lanza killed his mother in her home in Newtown's Sandy Hook community, after which the school takes its name. Adam was living with his mother, two law enforcement sources said. The other son, Ryan, was living in New Jersey.

Said Cullen, struggling to make sense of the weaponry and the carnage: "Something doesn't add up."

Marsha Lanza, an aunt to Adam Lanza, described him as a "quiet, nice kid," but he had issues with learning, she said. Her husband is brother to Adam Lanza's father.

"He was definitely the challenge of the family in that house. Every family has one," she told CNN affiliate WLS. "They have one. I have one. But never in trouble with the law, never in trouble with anything."

She said Adam Lanza's mother "battled" with the school board and ended up having her son home-schooled.

"She had issues with school," said Marsha Lanza, who lives in Crystal Lake, Illinois. "I'm not 100% certain if it was behavior or learning disabilities, but he was a very, very bright boy. He was smart."

Nancy Lanza was a giving, quiet, reserved person who grew up on a farm in New Hampshire with three siblings in a self-reliant family, Marsha Lanza said. The Lanza family is from Kingston, New Hampshire, she said.

"She didn't have to work because my brother-in-law left her very well off, very well off. She was always there for her kids," Marsha Lanza added, referring to Nancy Lanza's financial situation after she and her husband divorced.

The gunman's mother owned guns for self-defense, the aunt said.

"She never felt threatened, or she would have said something," Marsha Lanza said.

The aunt also said she couldn't begin to understand the mass shooting.

"Why these kids, why these innocent little kids? That just still baffles me," she said. "I can't understand why."