All day and into the night, they waited for news. Inside a three-bedroom home in Prince George’s County, Sylvia Frasier’s parents and siblings gathered, hoping to hear something about her fate.

The family had not been able to reach Sylvia, a 53-year-old network security administrator with the Naval Sea Systems Command, since they’d heard about the mass shooting at the Washington Navy Yard on Monday morning.

The Frasiers prayed and watched the live TV coverage. They clutched their iPhones and clasped one another’s hands every time a cellphone rang or beeped with a text message. Their minister came over, and everyone sat on the couches and sang from the Bible.

By 7 p.m., there still had been no word on the whereabouts of Sylvia, who lived in Charles County and was the second-youngest of James and Eloise Frasier’s seven children.

“My heart is beating so fast,” said Wendy Edmonds, 52, the youngest of the siblings and a college professor. “Dad knows something’s wrong since all the children are coming over. It’s the middle of the day. We’re supposed to be at work, not here at their home.”

The shooting at the Navy Yard left at least 12 dead, in addition to the suspected gunman, 34-year-old Aaron Alexis. It also left more than one Washington area family in a terrible limbo.

Another Navy Yard worker who remained unaccounted for Monday night was Mary Knight, an information technology specialist who also taught at Northern Virginia Community College, according to her professional profile. A call to Knight’s family in North Carolina was returned by a family representative, Theodore Hisey.

The family hadn’t heard from Knight since Sunday, Hisey said. They hadn’t been able to reach her Monday, and their calls to the Navy and hospitals had produced no information. She normally would have been in the building where the shooting occurred, he said.

Hisey described the ordeal as “very upsetting” to Knight’s family.

At the Frasier family home in Lanham, where Bibles adorn the bookshelves and crosses hang from the walls, Edmonds and her parents burned with questions: Is Sylvia alive? Injured? They were relying on news conferences, evening news reports, and phone calls and texts from other siblings searching the Navy Yard and designated parking lots for Sylvia.

The family was especially frustrated because they had spent all day calling the phone lines advertised for families of potential victims. But each time Edmonds or other relatives called, no one answered. Or the voice mail went to an automated recording for military support services.

“I have called that number too many times,” Edmonds said. “Six, seven, eight times.”

Because Sylvia is unmarried, the family expected James and Eloise, both in their 80s, to be contacted by the Navy or some other government agency.

Edmonds said she learned about the shooting about 9:15 a.m. from a sister who had seen news reports.

Edmonds texted Sylvia: “Are you okay?” she asked at 9:26 a.m.

No response.

The Frasier children began e-mailing one another.

“I have not heard from Sylvia, and she probably can’t call right now. Let’s keep her and everyone that works there in prayer!!!” wrote her sister, Maria Moore, a benefits analyst for a government contractor.

Several hours passed. By 7 p.m., most of the family had gathered at the parents’ home, where the Frasier children had grown up. At 7:10, Edmonds’s phone rang, and she grabbed it.

“Hello?” Then she hung up, shaking her head. It was a call to confirm her father’s upcoming doctor’s appointment.

At 7:30, the family’s minister, David Harrington, stopped by and led the family in prayer. They turned the TV volume down while they implored God for help, but kept the set on in case there was news.

Edmonds’s phone rang again. It was the third-oldest sibling, Lindlee Frasier, calling from the District.

“Okay, Sylvia’s in the hospital. She’s injured. The FBI talked to me,” Lindlee told Edmonds. Authorities said they were trying to figure out which hospital she’d been taken to and how badly she was hurt.

Edmonds worried that Sylvia might be more than injured. She tried to prepare her family for the worst.

“No matter how we feel, no matter what information we get from the FBI, we have got to forgive,” she said. “We have to forgive. We can’t become bitter.”

Moore shook her head. Investigators and reporters had chased down so much information on the suspect, but nothing on the victims.

“They found out who the shooter was real quick,” Moore said.

Finally, shortly before 10 p.m., Lindlee and a brother arrived at their parents’ home with news they couldn’t bring themselves to deliver by phone: Sylvia was dead.

“He killed my sister!” Edmonds cried.

Steve Hendrix contributed to this report.