Modie Lavin's son Marine Corporal Conner Lowry was killed in combat in Afghanistan on March 1, 2012.
"I saw three Marines there, and I just approached them slowly thinking why are you here, and knowing just deep down inside why they were there. And I just felt my body go into shock," Lavin said.
She says her son joined the Marines because he loved America and wanted to serve his country.
The 24-year-old Marine grew up in the Beverly neighborhood and was a graduate of Brother Rice High School.
Lavin says it's been hard since her son died, but she says he would want her to live by his favorite motto: to live life large.
"I knew my life would never be the same, and it hasn't been," she said. "But I'm doing my best because I know he'd want me to move on, be a bigger than life personality."
Coins have been placed on Lowry's grave throughout the day.
A penny signified that you are a fellow marine, a nickel means you went through boot camp together and a quarter signifies you were there when the Marine whose name is on the tombstone was killed.