Three names were added to the Massachusetts Law Enforcement Memorial during a ceremony at Ashburton Memorial Park in Boston on Friday.
Both Chesna and Gannon died in the line of duty in 2018. Moody died in 1932.
"It's terrible, and I never want anyone else to feel and experience the pain that my family's been feeling for almost 15 months," said Cindy Chesna, Chesna's widow.
"It's always painful. There is no healing of this kind of wound," said Denise Gannon, Gannon's mother. "But a bomb does come when you're surrounded by people who are experiencing the same thing that you're going through."