Lydia Bradford spent her last moments preparing for her 7-year-old daughter's birthday party.
It was around noon on Jan. 21, Martin Luther King Jr. Day. Neighbors had been in and out of Bradford's Cocoa, Fla., apartment all morning, helping her get ready, police said. The front door was left open. Cake was on the way.
In a front room, the birthday girl and her two little sisters, 1 and 4, played with a friend. Suddenly, a man with a gun burst inside, scaring the girls away, police said. As he moved into the house, the girls ran to a neighbor's and began pounding on the door. The neighbor answered, and as the children tried to explain what happened, shots rang out.
Bradford, a single mother with a gleaming, infectious smile, grew up in the area and studied at a nursing school aimed at helping young women put their careers on track, a relative said. She'd found work, and had recently moved into the apartment with her mother. She filled her Facebook page with self-portraits and snapshots of herself with her daughters. When she wasn't working, she focused on family: cookouts, card games, kids' birthday parties. Bradford loved kids' birthday parties.
But on this Monday afternoon in Central Florida, Bradford became part of a gruesome statistic.
She was one of at least 91 people killed by guns in the United States during the Martin Luther King Jr. Day weekend. NBC is examining those deaths as the nation continues to debate gun rights in the aftermath of the Dec. 14 Newtown, Conn., school shooting.
The intruder found Bradford and her mother, 58-year-old Equaller Bradford, in the back of their apartment. He sprayed them with gunfire. Equaller, hit in the face and chest, staggered outside and collapsed on the front lawn. Inside, Bradford lay mortally wounded, bleeding from her upper body.
While the children fled to a neighbor's, a second neighbor heard the pops, looked outside, and watched a man run from the scene, leap over a wooden fence and disappear. People were screaming. Someone was crying, "No, no no." The neighbor dialed 911.
"I got a lady laying out on the lawn out here," he told a dispatcher. "They're saying there's a lady shot inside…"
Another man called 911 from Bradford's apartment and asked for an ambulance at 1524 Clearlake Road, the Longwood Apartments. "Please hurry," he said.
In the background, a woman howled, "She's dead, she's dead." The dispatcher asked who did it. The man called out to the woman: "Did you see who did it?"
"A man with a ski mask on his face came and opened that door and just shot 'em," she yelled.
Medics loaded Equaller Bradford onto a helicopter that took her to a nearby hospital. Police combed the neighborhood on foot, by helicopter and with dogs, which traced the killer's path along the fence, but lost the scent. They did find a discarded handgun, which is being examined to determine if it was the murder weapon, and if it will lead back to the killer.
Bradford's family buried her Feb. 2. Her mother remained in intensive care, and could not attend. The audience included the lead detective, who "was devastated" by the sight of the weeping daughters, Cocoa police spokeswoman Barbara Matthews said.
"Our investigators have taken this case so personally," Matthews said.
Cocoa, she explained, is a small but economically diverse town near Cape Canaveral, with barely more than 17,000 people, some of whom live in public housing and others who live in multimillion houses. There were a handful of murders last year. Bradford's was the first of 2013.
Bradford's daughters have been taken in by relatives, said the family's pastor, Randolph McGhee. Although they did not witness their mother's death, they were among more than 40 people interviewed by police. There have been no arrests.
McGhee, who'd known Lydia Bradford since she was a young girl, said she "grew up in the church" and was "a good mother to her kids."
"She was a very fine young lady, conducted herself like a very fine young lady," McGhee added.
Why someone would kill her, that remains a mystery.
"As far as what happened to her, who knows if it was random or this or that," McGhee said. "We can't say why."
With reporting by NBCNews.com's Tracy Connor.