"I just thought, 'I'm so sick of this. Those kids are the same age as Jordan and are being gunned down. Why are our legislators still playing games with human lives?'," she says.
Six years later, McBath's fight for justice and gun reform continues to evolve.
As she connected with families of the Parkland school shooting victims in February and continued lobbying on behalf of the gun control group Moms Demand Action for Gun Sense In America, McBath realized the massacre struck too close to home.
She prayed to God for guidance about what she should do to help the students. Two days later, she decided to run for Congress.
In March, McBath added her name to the Democratic primary ballot for Georgia's 6th -- a district made up of northern Atlanta suburbs. On Tuesday, voters will decide which of the four Democrats will run against Republican Karen Handel in the general election in November.
McBath stands out among her party opponents as the only person of color and the only woman.
Kristin A. Goss, a public policy professor at Duke University who has been studying the gun debate since Columbine, says McBath's path to politics is not unusual.
Former US Representative Carolyn McCarthy led the fight on the Democratic side of the aisle for years before retiring. She had been living a quiet life as a nurse in 1993 when a man killed six people on a Long Island commuter train, including her husband. The incident eventually led her successful election to Congress.
McBath is also joining a wave of women across the US who are stepping up to run for school boards, city councils and state houses. Like her, many have lobbied for gun control laws.
"What many of our volunteers realize after visiting their state or federal lawmakers is that they are just as smart and capable," says Shannon Watts, founder of Moms Demand Action.
Last year, nine women involved with the group ran for local and state office and were elected. This year, dozens more are following their footsteps, Watts says.
Turning grief into action
McBath recalls sitting on a couch -- some 1,000 miles away -- crying and screaming after she learned that Jordan was killed.
It was the day after Thanksgiving in 2012.
She had been visiting family in Chicago when Jordan's father, Ron Davis -- who he had lived with in Jacksonville, Florida -- called to break the news.
Jordan and three of his friends were on their way to the mall when they stopped at a gas station to get gum and cigarettes. Dunn was parked next to the teens' red Dodge Durango.
He didn't like the loud music -- "rap crap," as Dunn described it during his trial and asked them to turn it down. Shortly thereafter, he began shooting, striking Jordan three times.
Jordan's death unleashed a whirlwind of events and helped revive the activist inside McBath, who had been living in Georgia since becoming a Delta flight attendant in the early 1990s.
She started questioning lawmakers, the clergy and anybody who would listen. She appeared on TV telling her story, attended rallies and knocked on doors on Capitol Hill.
"Oh my Gosh (sigh), my life today absolutely nothing resembles, in no way, shape or form my life before Jordan was murdered," she says.
McBath also attended Dunn's trials, learned about gun control laws and met with other survivors.
"I began to notice that I was no longer interested in flying. When I would go to work my mind was everywhere else," she says.
Two years after her son's death, Dunn was sentenced to life in prison without parole
. A jury found him guilty on multiple charges, commanding at least 60 years in prison, but the jury was hung on the murder charge related to Davis' death.
Dunn sought to use the controversial Stand Your Ground law as his defense, saying that Davis threatened him and that he thought he saw a gun sticking out the teenagers' SUV. Police found a basketball, sneakers, clothing, a camera tripod and cups inside the vehicle, but no gun.
After a second trial, Dunn was convicted
of first degree murder.
Dunn's conviction gave McBath a "limited sense of justice."
"It's not enough justice won because I don't have my son, and two, because there's so many other people in this country that continue to die like him," she says.
So she continued telling her story as a way to keep her son's name alive in people's minds even if it meant reliving her pain.
"For me I was looking beyond my own tragedy, looking for the other tragedies that were most definitely going to happen if I didn't keep talking about this crisis," she says.
And after nearly three decades as a flight attendant, she decided to retire in 2014 and became a national spokeswoman for Moms Demand Action for Gun Sense In America.
Since then, she has traveled around the country to speak with lawmakers, meet survivors of gun violence and even campaigned for Hillary Clinton
"My sense of purpose before was raising my child and making sure that he had what he needed to become a successful human being," McBath says. "Now, my purpose has shifted."
Raising a young black male
In 1994, McBath had given up on ever having a child due to several miscarriages when her "miracle baby" began growing inside her.
"I was very, very careful. Just didn't want to slip, didn't want to fall," McBath recalls. "I did exactly as the doctor told me to do."
She dedicated her life to raising Jordan. The curious boy with a great sense of humor loved learning about everything around him. He disliked math but loved history and social sciences, and he was the one friends went to for advice, she says.
The killing of Trayvon Martin in February 2012, McBath says, forced her to have the talk with her son about how to live and survive as a young black male in America.
"I remember having that discussion with him telling him, 'Sweetheart, because you're a young black male. You know, there are a lot of people in this world, in this nation that don't value you,'" she recounted. "'And you have to be so careful where you go and what you do and who you talk to, because you know if you get into an altercation with anyone nowadays people will take their guns out, and they'll shoot you.'"
Nine months later, he was shot and killed.
"I wasn't going to be quiet. I wanted everyone to know that Jordan was a good kid," she says. "Jordan didn't deserve to die that way."
Running for office
McBath says one of her biggest challenges to date began a few months ago.
She had been campaigning for a seat in Georgia's House of Representatives -- a race she felt comfortable in -- when the Parkland shooting happened and in a leap of faith, she decided to run for Congress instead.
McBath hopes to unseat Handel, who is seeking reelection to a full term after she edged out her Democratic opponent, Jon Ossoff, in a runoff election in 2017 that turned into the most expensive House race in history. More than $50 million was spent by both parties and super PACs.
But McBath is prepared for the challenge.
She's picked up endorsements from several gun control groups and EMILY's List, a political action committee that backs Democrats who support abortion rights.
And while Jordan's death may have been the catalyst to her activism; politics and the fight for civil rights played an integral part of her youth. She was born in the Chicago suburb of Joliet, Illinois, and grew up traveling with her family to rallies around the state.
As a teen she dreamed of attending law school or becoming a lobbyist. In college, she interned on Capitol Hill for the NAACP, and worked as an aide for then-Democratic state senator Douglas Wilder in Virginia.
Since entering the race for Georgia's 6th congressional district, McBath has been forced to expand her knowledge and deep dive into foreign policy, healthcare and other topics being discussed out of the White House and Capitol Hill.
'My life's mission'
"I'm learning very rapidly. I just feel like the pace has accelerated while I'm running for office," she says.
For Michael Owens, the Democratic Committee Chairman in Cobb County -- on the western side of the 6th district -- McBath's prominence in the national political round may contribute to keep the momentum going for Democrats in Georgia.
"Lucy has the ability to connect with people. In a room full of people I think she can connect with people one-on-one," Owens said.
Bobby Kaple, who quit his job as a local news anchor to enter the race, is centering his campaign around affordable healthcare and has declared his support for Obamacare. Kevin Abel, a businessman who immigrated from South Africa as a teenager, has criticized President Donald Trump's position on DACA and refugee settlements. And Steven Knight Griffin, a former policy expert at the Centers for Disease Control and Prevention, also left his job in the hopes of running against Handel.
All of them support gun control laws but McBath has made it her campaign's top issue.
"This is my life's mission, to make sure we put common sense solutions in our existing gun laws, beyond just making sure that people live the way our constitution says they are supposed to live," McBath says.