"We never had any problem," she said Monday of her neighborhood.
The death of her son has made her feel differently.
"Now I know there not safety anymore for me, for my family," said the Vietnamese immigrant who works as a manicurist.
Tai Lam was killed Nov. 1 when a man fired several shots into a county Ride On bus at a stop near the intersection of Piney Branch Road and Arliss Street in the Long Branch neighborhood of Silver Spring. Two other boys, ages 14 and 15, were also shot but survived their wounds.
Police say the shooting resulted from a verbal exchange between a group of youths Tai Lam was riding with and three to four men who got on the bus at two stops in Silver Spring.
On Friday, police charged Hector Mauricio Hernandez, 20, of the 8600 block of Flower Avenue in Takoma Park with first-degree murder. A Montgomery County District Court judge said Hernandez, an illegal immigrant, was a flight risk and denied him bail. On Monday, police issued arrest warrants for two other men. Gilmar Leonardo Romero, 20, will be charged with first-degree murder, and Mario Ernesto Milan-Canales, 30, will be charged with accessory after the fact for first-degree murder.
Police say the men have ties to the Salvadoran gang MS-13.
While police have made progress in the case, Ngoc Lam said she senses anger in the community. She fears something else will happen to her 16-year-old son, Lam Cao, or his friends at Montgomery Blair High School.
After Tai Lam's burial on Saturday, Ngoc Lam said the nights are long and dark. She said Lam Cao, who shared a room with his brother, doesn't want to get rid of Tai Lam's belongings. Some of Lam Cao's friends from Blair visit the family and sleep on the floor at night to comfort him, she said.
"He lost everything," she said of her oldest son, who witnessed the shooting. She said it is difficult for Lam Cao to ride the bus to and from school every day without his brother by his side.
Still talking about Tai Lam in the present tense, Ngoc Lam said her son was the talkative one in the family.
"He got something he want to know, he ask a lot of questions. He's so nosy," she said.
But Tai Lam made it a point to tell her how beautiful she looked every day and was good at lifting anyone's spirits.
Tai Lam was a popular freshman at Blair High. At the school's homecoming football game Friday he was posthumously named "Homecoming Lord," a title he campaigned for while still alive.
A poster sits in the school's main hallway, open for anyone to write a message about Tai Lam or words of comfort to his family. Since Nov. 5, counselors, psychologist and county government officials have visited the school to assist the students and staff, according to a letter from Blair Principal Darryl Williams that was sent home Friday.
In a Monday night community meeting held at Blair, several high-ranking county officials told a crowd of about 200 residents that the community must be proactive in preventing violent crimes and keeping youth safe.
"We seem to find strength and the will to come together after the fact to talk about what we could have done," said County Executive Isiah Leggett (D). "But we tend as a community to lack the will to come together more often prior to these type of events."
Most of the discussion focused on keeping youths out of gangs. Montgomery County State's Attorney John McCarthy said the peak hour for youth crime is between 2 p.m. and 6 p.m. on school days.
Williams said after-school programs like the Blair Sports Academy attempt to keep students off the streets.
"We try to have an outlet for students," Williams said. "They join gangs because they don't feel a part of something."
A video including photographs of Tai Lam and testimonials from fellow students was shown. A poetry slam event will be held at the school Tuesday to honor Lam and an anti-violence concert is being planned.
More than $5,000 was raised during school lunches to help the Lam family. Tai Lam's sister, Quy Lam, praised the Victims Rights Foundation for offering a $5,000 reward for information about the case.
"Through a great loss we found the heart of the community is the best of all," she said.
Lam Cao asked law enforcement officials how his brother's alleged killer would be prosecuted and sentenced if convicted.
Leggett said it was important to prevent backlash against the Latino community because of the alleged gang affiliation of the men police believe were responsible for the shooting and the status of the man charged as an illegal immigrant.
"This is more of the exception than the rule in the county," Leggett said.
Blair junior Fernando Rivera, a friend of Tai and Lam Cao, said there needs to be better trust between communities and police.
"The communities affected by gangs are Latino and black," Rivera said. "There is lots of police brutality in those communities."
The responsibility falls on youth just as much as police to prevent violence, said Blair sophomore Adam Ndiaye.
"We need to be careful of who we are dealing with," he said. "We need to watch out for each other."