Richard Sowell, 7, left, smiles at his grandmother Olivia Chase, 60, after she picked him up from Thomson Elementary School in Washington, D.C. (Christian K. Lee/The Washington Post)

The medicated patches that are supposed to numb the pain in Olivia Chase’s knees won’t stay affixed, so she adjusts them, once again, and pushes forward on her rolling walker.

She has to keep walking.

She walks at 7:30 a.m. to catch a bus to take her 7-year-old grandson to summer school. She walks at noon into her church to drop off his camp registration form. She walks at 5 p.m. to pick him up from school and take him to swim practice. She walks and walks, until 7 p.m., when, finally, she and her grandson step into the one-bedroom apartment they share in Northwest Washington, a place where there is no room to entertain company because the living room is his bedroom.

“Sometimes I go until I can’t go,” says Chase, who is 60.

The walls have not yet been erected on a plot of land in Mount Vernon Triangle for a 12-story ­affordable-housing development, but Chase and others are already hoping it will serve as a refuge for families such as theirs: grandfamilies.

Richard Sowell, 7, talks to another swimmer before jumping into water at Banneker Pool. (Christian K. Lee/The Washington Post)

The building will be the first of its kind in the city — and one of only a handful in the nation — offering subsidized housing and services for grandparents raising grandchildren.

It will be a place, developers and city officials say, designed for two vulnerable populations: those growing up and those growing old.

“This is as big a problem as homelessness or anything else we’re facing right now,” said Daniel Henson, a developer behind the $84 million project, which will be funded with public and private dollars. Fifty of the 223 apartments for low-income residents will be set aside for grandfamilies.

“I’m hoping we can be a model, and we can begin to address what I think is a major issue moving forward,” Henson said.

Nationally, the number of grandfamilies — about 2.7 million at last count — appears to be growing because of the ­opioid-addiction crisis and the priority that child-welfare agencies now place on keeping families united, experts say.

In the District, where rising real estate costs pose a heavy burden on low-income residents, about 1,000 grandfamilies need subsidized homes, officials estimate.

Chase has already contacted city officials to ask how she can apply to be among the first residents when the project known as Plaza West opens in 2018.

An architect’s rendering of Plaza West, which will offer 50 apartments for grandparents raising grandchildren, near Union Station. (Hickok Cole)

Finding services in one place that she and her grandson currently seek across the city would shorten their often-long days, she says. And then there is the benefit of having neighbors with similar family structures.

“When you’re in school and you see a lot of mommies and daddies, even though you know you have your grandma, I think there is still a void,” Chase says. “But being in an environment where you see people are just like you, it gives him a different window to look out of, a different sense of identity.”

This hit her as they sat in a movie theater on a recent evening, watching the animated film “Finding Dory.” The blue tang fish, voiced by Ellen DeGeneres, was just about to meet her parents when she realizes they aren’t where she thought they would be. Chase looked over and saw her grandson in tears.

‘Will I be here?’

On a Monday morning, Chase is the first to arrive at a support group tailored to grandparents who are raising grandchildren.

She didn’t plan to be here at 60, sitting at a table topped with pastries and juice, discussing how season passes to Six Flags work.

Chase raised three boys alone while working as a nuclear medicine technologist. Her oldest son lives in California and her middle son in New York. She watched her youngest son, Oliver Sowell, join the military, serve in Iraq and come back “much different than he left.” In 2010, he was convicted of capital murder in Texas and given a life sentence without the possibility of parole. His wife, who was also involved in the incident in which a woman was fatally shot outside an illegal gambling room, was sentenced to 48 years in prison. The two had been staying with Chase before their arrest and left her to care for their infant son, Richard.

“I was 53 years old with this 3-month-old baby and really in shock,” recalls Chase, who has received disability payments since 2002. She knew nothing about day care when someone suggested she enroll the child in a program at Martha’s Table. Richard was 11 months old when President Obama visited the center and lifted him up. Chase shows off a picture of the moment that she keeps on her phone.

The six grandmothers at the support group all brag about their grandchildren, even as they vent about them.

“I have to share this, y’all,” says Cassandra Gentry, 64, who sports a short crop of white hair and silver hoop earrings. She tells how the music instructor at her grandson’s school asked to meet with her after his performance in a 1970s-themed production. “She said, ‘Brace yourself, you have a natural-born actor.’ ”

The women swap stories and laugh about how boys don’t like to share beds and how children nowadays prefer 7-Eleven pizza or carryout drenched in mumbo sauce over home cooking.

But in other moments, the conversation turns serious. One grandmother says her 22-year-old grandson still asks for money, and she’s tired of giving it. When another woman asks whether her grandchild will receive her Social Security benefits when she dies, the woman next to her says the only reason her own grandchildren are entitled to hers is because their father killed her daughter and then lost his parental rights.

Organizations that work with grandfamilies say that often these families are forged through death, drugs or other traumatic circumstances.

Donna Butts, who heads the District-based Generations United, says her nonprofit organization advised city officials that support services had to be integrated into the Plaza West project for it to succeed.

Grandparents who step up to take care of their grandchildren are twice as likely to live in poverty as their peers, and they are also more likely to say they skipped a meal or medication to provide for the children, Butts says.

At the same time, she says, they save taxpayers more than $4 billion a year nationally by keeping their grandchildren out of the child-welfare system.

“People need to realize we all have a stake in this issue,” Butts says.

At the support group, run by Howard University’s School of Social Work, the women talk about the children in their lives, but also about themselves. They discuss fears, and hopes.

“I wonder will I be around for him,” Gentry says. “I lost a lot of friends these last two or three years. They just checked out of here, 64, 65 years old. And I’ll be 70 when this baby graduates. Will I be here?”

Chase says she has started to think about “life after Richard.” She’s going back to school, she tells the group.

“I still want my life to be useful up until whenever that is, you know, the end,” she says. “You know 60 is the new 30. In this city, really, this city is age-friendly, they are age-supportive. In many ways, I feel this city is my family.”

‘This has to go deeper’

The concept for Plaza West grew out of a family. Yvonne Williams says her father, Smallwood Williams, the founder of Bible Way Church near Union Station, had a vision for the strip of land near K Street and Interstate 395 before he died in 1991. He wanted to see the grounds used for an intergenerational center.

“He left us with that core concept,” says Williams, 77. He couldn’t have known then how the crack epidemic would leave an increasing number of grandparents raising grandchildren or how opioids would do the same decades later. “We started to say: ‘This has to be more than a community center. This has to go deeper than that.’ ”

The church, which has created 500 affordable-housing units in the city, presented the concept to developers it had partnered with previously. The result is Plaza West.

At a groundbreaking ceremony last month, D.C. Mayor Muriel E. Bowser (D) lauded the project. “Plaza West shows us what is possible when we work together,” she said. About $20 million in public funds will be used for the project; the rest is coming from private investment.

Sarah Constant, managing director of Mission First Housing Group, says the number of units is limited to 50 because research indicates it is the ideal size. The grandfamily section will have its own entrance and amenities, including 24-hour concierge service, separate play spaces for children of different ages and a library where grandparents can gather.

Williams has high hopes for the development. “I’ve already asked the Lord in heaven, ‘We want some Harvard scholarships as well as Howard scholarships,’ ” she says. “It’s not just getting your high school diploma. It’s expanding horizons.”

‘They have to have shoes’

Addie Brinkley, 62, just wants a place where smoke from cigarettes and marijuana won’t seep into her home and trigger her granddaughter’s asthma.

In the hotel where she lives with the 12-year-old and the girl’s 10-year-old sister, there is no escape from it. But they have little choice.

For 14 months they have been homeless, living in city-provided temporary housing. Brinkley works in the mailroom at the National Institutes of Health, where she has been employed for 42 years, but she says her paycheck is not enough to support three people. She also says she doesn’t qualify for a monthly stipend from the city’s Grandparent Caregiver Program. Currently, 492 caregivers, including Chase, are enrolled in the program.

“They say, ‘God don’t put more on you than you can bear,’ ” Brinkley says one recent afternoon. The 12-year-old is in summer school, but the 10-year-old had to join Brinkley at work because she doesn’t have alternative care.

When the girls came to live with her nine years ago, Brinkley says she was working two eight-hour jobs as well as part-time security work and had to quit all but the NIH job. Opportunities to advance arose there, but she says she couldn’t take advantage of them because she couldn’t read. Now, she’s trying to earn a high school diploma.

“I can survive for me, but you got to make sure these kids are well taken care of,” she says. “If I don’t buy myself a coat, they have to have coats. If I don’t buy myself shoes, they have to have shoes.”

Chase knows sacrifice, too. But as she pulls herself slowly from a public pool one afternoon and sits on her walker, she isn’t thinking about her aching knees that should be replaced. She thinks about how the boy speeding through the water in neon green shorts keeps her moving. “I probably wouldn’t be swimming if I didn’t have him,” she says. “I wouldn’t do a lot of things if I didn’t have him.”

She wouldn’t be on the PTA, or know about Minecraft, his favorite video game. She wouldn’t know how to “whip and nae nae” or be planning to chaperone a camping trip to North Carolina.

She wouldn’t be smiling proudly, even as the rain starts falling at 6:30 p.m., as she shows off a shirt Richard gave her after completing a 5K run. It reads, “We are D.C.”