She later learned at the memorial service that Jenkins, too, was a fan of movie and TV trivia and collected original movie posters.

“I always meant to ask him about it,” Clark says. “I wish I had.”

Layla Cable says she feels a similar nagging regret of a missed opportunity at friendship, particularly after hearing poignant anecdotes from Jenkins’ friends at the Monday night service.

She learned about his love of collecting things. His house was a veritable archive for old copies of The New York Times dating back 20 years.

“I think there was a side to him I never knew about. We just knew him as smiling John, the guy who’d always stop to chat or touch a cat or talk to a kid,” Cable says. “But I never had dinner at his house and he never had dinner here.”

She pauses for a second. “Sometimes you keep putting things off.”

Cable says she is hoping that, if nothing else, last week’s tragedy could make the families on this comfortable, tree-lined street less isolated. At the risk of sounding cliche, Cable says, she’s also reminded at how fragile life is.

“Maybe one thing that would come out of this is that people will start paying more attention to their neighbors,” Cable says. “You never know when they’re going to need you...or just not be there any more.”

—Staff writer Daniela J. Lamas can be reached at lamas@fas.harvard.edu.