SAN DIEGO — A 35-year-old mother of three children was the lone person killed by a despondent gunman who police said shot seven people at a poolside birthday bash in San Diego after a breakup with his girlfriend.

A childhood friend said he will miss the infectious smile of victim Monique Clark, who was devoted to her daughters, ages 2 to 13.

“She had such a great personality,” said Vincent Howard, who met Clark in high school. “She was always smiling. She was always with her kids and everyone else’s kids. She was like a mother to them all.”

Clark also helped homeless people, volunteering often at food drives.

Entertainer Nick Cannon, a childhood friend of Clark, tweeted, “my heart hurts with great sadness.”

Authorities say Clark was shot and killed Sunday by 49-year-old Peter Selis, who was angry over the recent breakup and called his ex-girlfriend during the attack so she could hear him shooting strangers.

Officers killed Selis in a shootout at the upscale apartment complex.