Keith Darnell Williams Sr. liked being a custodian of an elementary school in the District because he liked to help children.

His focus didn’t change when he joined the D.C. police force in 1989. On patrol, his first stop was always the boys and girls clubs, and he spent much of his 31 years on the force mentoring students as a school resource officer.

He retired in 2017 but returned under a senior officer program to help the department, and once again was assigned to a school.

Williams was hospitalized with covid-19 in March and died June 4.

He is believed to be among the first of more than 150 officers on the D.C. police force to test positive for the novel coronavirus and the only one thus far to die. He was 53.

“Whether on the foot beat or in a hallway at school, he made it his business to know every person, whether it was the local store owner or a teacher,” Police Chief Peter Newsham said at Williams’s funeral Mass on June 29 at Saint Martin of Tours Catholic Church on North Capitol Street in Northwest Washington.

“He knew those on his beat who were down on their luck, suffering mental illness or addiction,” Newsham said. “He took medication to elderly members of the community when they couldn’t get to the drugstore. He checked in on schools, he coached basketball and helped in the cafeteria at lunch. He was the kind of dedicated police officer that each community wants.”

Williams worked three decades worth of Fourth of July celebrations on the Mall, seven presidential inaugurations, visits from two popes, the Sept. 11 attacks, the mass shooting at the Navy Yard and the championship runs for the Nationals and the Capitols.

“It has been suggested that we take school resource officers out of our schools,” Newsham told mourners, noting the current demonstrations over police violence and calls to defund the police. “What I would say to them is they never met Keith Williams. If they had met Keith Williams, they would know the thousands of young lives he was productive in.”

Williams’s former partner on the force and longtime friend, Edwin Buckner, said that “if you want to talk about community policing, and being in the neighborhood and being about your people, Keith Williams was all about that.” Even before the debate over race and policing that rages today, Buckner said Williams would say, “We’re all in this together, as black folks, we got to start treating people nicer.”

Williams grew up on Montana Avenue in Northeast Washington — his father worked for the Postal Service, his mother as a building engineer for D.C. public schools. He attended St. Martin’s Catholic School, where he played for the Mustang basketball team. He graduated in 1985 from DeMatha Catholic High School in Hyattsville. He joined the Marines and then worked for the school system before he joined the police force.

He married Sandra Myrick-Williams in 1993; the couple raised two daughters and five sons in Prince George’s County — dubbed “The Williams Clan.”

Williams, with his big smile and big heart, was addicted to telling stories, sending random texts — often updating people about his children’s achievements in real time — and performing practical jokes.

In police locker rooms, he would find lockers left open, and turn the padlocks upside down and secure them.

Longtime friend Clayton Mills recalled playing a practical joke that scared Williams when both were kids, and then how Williams got even years later by pulling up in a squad car, training his spotlight on Mills and pretending he was going to arrest him. Mills, blinded, didn’t see Williams approach him and immediately thought, “I got to call Keith. He can get me out of this.”

Even his wife of 27 years wasn’t immune. Sandra Myrick-Williams said she suspects somebody — maybe her husband — briefly put on a pair of her socks and stretched them out. Later, Williams joked in front of the family about how big the socks were, as if a “giant foot” had been stuffed inside.

“He was something else,” his wife said.

The couple met hours after Myrick-Williams had bought a new car and was shopping for accessories in a Discount Mart in Northeast. Williams was working an off-duty security shift and, apparently attracted to this new customer, followed her around the store.

“When I left, he said, ‘Can I help you with your bags?’ I said, ‘You sure can.’ ”

Myrick-Williams said her husband’s personality “was one of a kind,” and that he was always heading off to play basketball or some other sport. Often, she said, he’d return home for meals with a bunch of children. “I’d say, ‘But they’re not my children and you keep bringing them here.’ ”

But his wife said it was all worth it. “I’ve seen some children that because of him have made a tremendous transition going forward in life,” she said. “For those who didn’t get to know him, they missed out on something.”

Williams became sick in March, just after the D.C. area began shutting down and people started working from home. He thought he had a sinus infection, and eventually was diagnosed with pneumonia. Still, health care workers told him he didn’t exhibit enough symptoms to get tested for covid-19.

On Sunday, March 29, Williams went to a hospital, was diagnosed with the coronavirus and started to deteriorate. Myrick-Williams spoke to him two days later, at 7:46 on a Tuesday morning. “I told him to pray. He’s always been a fighter. I told him, ‘You’ve been fighting all your life. You’re a Marine. You’re a police officer. Pray and you’re going to get through it.’ ”

Williams was put on a ventilator about two hours later.

He remained on the machine for the next 65 days.

The couple would never talk again.