LEWISTON, Maine — For the family of the Army reservist who carried out a mass shooting across Maine's second-largest city one year ago , dissecting what provoked the deadly rampage has been daunting. Amid the heartbreak in Lewiston, where 18 people were massacred on the evening of Oct. 25, 2023, at a bowling alley hosting a youth night and a bar where deaf people were playing cornhole, the gunman's family contemplated remaining quietly in the shadows.

But the unspeakable violence inflicted on this community has spurred a very public purpose for the family: bringing awareness to traumatic brain injuries among military members and a call to action for continued research. Read more on this story at NBCNews.com and watch "NBC Nightly News with Lester Holt" tonight at 6:30 p.

m. ET/5:30 p.m.

CT. "We want to make sure this doesn't ever, ever happen again to another family," said Nicole Herling, the sister of gunman Robert Card. Card, 40, was found dead by suicide after an extensive two-day manhunt.

A firearms and hand grenade instructor and longtime member of the Army Reserve, Card shared a teenage son with his ex-wife. In the months leading up to the shooting, members of his family tried to get him help, including reaching out to a veterans crisis hotline about his erratic behavior and also placing multiple calls to his military base. They also noted he had complained about hearing voices when he was fitted for high-powered hearing aids and had a "manic belief" that people were a.