Lillash was a good friend of Parmertor, one of the teens who died, and said he "started crying uncontrollably" when he heard the news of his friend's death.
Another student, Lexi Joy, passed Lane in the hallway right before the shooting, saying they exchanged a smile and a nod, like usual.
"He didn't seem any different. He seemed just like he'd be on a normal day," Joy said. "He didn't show any expression on his face. He was just TJ."
Lane's family life had been disrupted by divorce and violence, ABC News affiliate WEWS reported. His parents divorced in 2002, and his father later served time in jail on assault and other charges, according to the station.
In 2002, Lane's father Thomas M. Lane pleaded guilty to a charge of felonious assault for pushing his ex-wife's head into a wall and strangling her until she lost consciousness for several seconds, according to court documents.
"[Thomas M. Lane] held victim's head over washing machine and poured cold water from a utility hose over her nose and mouth preventing free breathing," Deputy Charlene Sulak wrote in a complaint.
Attorney Robert N. Farinacci, who is representing Lane, released a statement on behalf of the family Monday night, according to WEWS, calling the incident "something that could never have been predicted."
"The family is devastated by this recent event. They want to express their most heartfelt and sincere condolences to the family of the young man who passed and their continuing prayers are with all those who were injured," Farinacci wrote. "TJ's family has asked for some privacy while they try to understand how such a tragedy could have occurred and while they mourn this terrible loss for their community."
Classes were canceled for all schools in the district today.
The school superintendent announced today that a Chardon Healing Fund has been started and that all money donated will be used to help those that have been impacted. A total of $150,000 has already been donated to the fund.
Chardon is a village in Geauga County, about 35 miles east of Cleveland.