Carol Glover in 2014 with sons Marcus, left, and Anthony Raymond "Ray" Glover. (Courtesy of the Glover family )

The knock on the door came about 10 p.m. Monday.

Marcus and Suzanne Glover were wrapping up the day at home in Alexandria, watching football on TV. They’d had dinner and put their daughter, Sara, to bed. Sara’s first birthday was Thursday, and a family party was scheduled for the weekend.

When they answered the door, two police officers were standing there.

The Glovers had heard about the Metro tragedy that afternoon in which a woman had died. They knew that Marcus’s mother, Carol Glover, 61, took that Metro line home to Alexandria from work every day.

Now, here were the police telling the couple that the woman who died in the Metro car that filled with smoke was Carol.

A Metro passenger filmed the scene inside the stranded Metro car, in which people can be seen helping and comforting each other. A Yellow Line train abruptly stopped and filled with smoke in a tunnel in downtown Washington on Monday. (Saleh Damiger/YouTube)

“It was a shock,” Suzanne Glover, 32, said Wednesday. “It was disbelief, I think, for both of us. . . . We were just speechless and trying to take in the information and process it as we were listening.”

Carol Glover, who was the mother of two adult sons, who had twice become a grandmother in 2014, and who was an anchor of faith and wisdom in her family, had died among strangers on her homeward commute.

Glover died of acute respiratory failure, due to smoke exposure, the District’s Office of the Chief Medical Examiner said Thursday evening. The office said the manner of death was accidental.

It was dreadful to hear the details of the incident but comforting to learn that fellow passengers ministered to her in what may have been her final minutes, Suzanne Glover said.

“Trusting in the Lord,” she would always say, Suzanne Glover recalled in a telephone interview Wednesday evening.

“She always just had a very calming effect,” she said. “She has this way about her of helping us to trust in the Lord in all of our circumstances and helping us to be grateful and calm.”

“She was really easygoing,” she added. “She was the type of person who was very independent and raised her boys to be really independent, strong thinkers.”

“She just cared for our family really well,” she said, “just a really great combination of strength and humility and kindness.”

Suzanne Glover, 32; Marcus Glover, 30; and his mother attended Washington’s Capitol Hill Baptist Church, where the couple met and where Carol was a welcoming figure.

“Her hope and confidence wasn’t in this world,” Suzanne Glover said in a later e-mail. “She always pointed us to our future hope in heaven.”

A memorial service is scheduled to be held at the church at 10 a.m. Monday.

As officials continued to investigate the incident at 3:15 p.m. Monday, in which smoke filled the tunnel outside the L’Enfant Plaza station and seeped into the cars of a stuck Metro train on the Yellow Line, a fuller picture of the sole fatality emerged.

Glover, a Washington native, was headed home from a U.S. Department of Agriculture site near the waterfront, where she had been working as a contractor.

Her family said she usually took the Metro to Pentagon City and then a bus to her home in Alexandria, where she had partly raised her boys.

Patrick Welsh, a retired teacher at T.C. Williams High School in Alexandria, said he taught Marcus Glover and his brother, Ray, 33, in an advanced English class there.

He said he knew Carol Glover from parent conferences and football games.

“She was kind of no-nonsense” with her sons, he said Wednesday night. “That’s why they were good, serious students. . . . She was just very witty and charming, just kind of a real with-it mother who kept on her boys, in the good sense.”

Carol Glover had been working as a senior business analyst with the Washington firm of DKW Communications Inc. for the past 18 months. Her job was to go into a client agency, study its business practices and suggest ways to improve.

Her supervisor at work, Cliff Andrews, said that Glover suffered from asthma. “I’m sure being in a smoke-filled car didn’t help,” he said.

“She functioned,” he said. “It wasn’t like she missed days because of it. . . . But I do know she suffered from asthma because she would talk about it.”

Carol Glover had worked hard and was given the employee of the year award at the company’s holiday party at the Ritz-Carlton Hotel in early December, he said.

“She had the ability to make people comfortable around her and suggest things without making people feel intimidated,” he said.

“She was a lovely and kind person — always came to work with a lot of energy,” he said Wednesday. “I nominated her for employee of the year because of some of her contributions on a project that she was working on . . . and she was selected.”

There was a monetary award and some additional “goodies,” Andrews said. “She was actually very surprised when she won it.”

Suzanne Glover said that her mother-in-law was thrilled to get the award.

“She said, ‘You know, I just try to do my best, and I try to work really hard and be good at what I do,’ ” she said. “She just seemed really excited to be acknowledged.”

Suzanne Glover said authorities on Monday had first notified Carol Glover’s mother, Corrine Inman, 86, of Washington, and then told other family members.

She said she and Marcus went to the medical examiner’s office Tuesday to identify her mother-in-law’s body because she had not been found near her belongings.

Authorities were fairly certain of her identity, “certain enough to come and deliver the news,” Suzanne Glover said. But they had to make sure.

This weekend, Carol Glover was scheduled to attend the small birthday party for her granddaughter, Sara.

“Instead of that, we’ll be planning the funeral,” Suzanne Glover said. “Which is definitely not what we expected.”

Brigid Schulte and Patricia Sullivan contributed to this report.