Sonia Palomo Figueroa, right, a family support worker at Mary's Center, works with Roxana Avelar De Andrade, 36, and her 2-year-old son, David, at their apartment. (Sarah L. Voisin/The Washington Post)

Roxana Avelar De Andrade was new to the United States, with two children and a third on the way. She was feeling stressed and overwhelmed, and during a routine prenatal care visit she burst into tears.

Her health-care provider at Mary’s Center in the District connected her to a support worker, who started visiting her family at home every week to check on her and see how she could help.

More than two years later, she has a curious, talkative toddler and a lot of gratitude for the steady support. “It made me not feel so alone,” she said.

Home-visiting programs, such as the one that Avelar De Andrade is involved in, pair low-income struggling parents with trained nurses, social workers or educators, who provide support throughout the stressful first years of their children’s lives. Through regular visits, the support workers provide resources to help families with basic needs and teach habits and skills to parents to promote the healthy development of their children.

These early-intervention programs have grown in the past few decades alongside research showing the first years to be a critical time for brain development. President Barack Obama included home visiting in his first budget, and the program got a jolt of federal funding through the Affordable Care Act in 2010 with $1.5 billion in state grants. The legislation, which has been extended twice, is set to expire at the end of the month.

Bills have been introduced in the House and Senate, and the program has bipartisan support. But now, with the clock running down, advocates are scrambling to get something passed in time to preserve these support services for an estimated 150,000 families.

“Family stability is what is at stake,” said Diedra Henry-Spires, co-convener of the Home Visiting Coalition, a group of organizations working to extend and expand federal support for the service. “This program has a reputation of providing families with stability.”

Federal dollars funded home visits for 1,175 families in Maryland in 2015 and 1,449 families in Virginia. They make up the bulk of funds for home-visiting programs in the District. In a city where nearly a quarter of children under age 5 live below the poverty line, advocates say home visiting is a promising — and already underused — strategy for addressing inequality early.

“We have home visiting in the District, but we do not have the reach we need to have,” said D.C. Council member Brianne K. Nadeau (D-Ward 1), who proposed a bill this summer that aims to expand local investment in the program.

A report released by the D.C. auditor this summer estimates there are 6,300 households with children under 5 that would benefit from home-visiting programs, based on risk-factor data including poverty levels, access to prenatal care and developmental delays. In fiscal 2015, just over 1,300 families — about a fifth of that number — were served.

Nadeau’s bill proposes a feasibility study of a public-private partnership to expand home visiting, in which investors would pay the costs up front, and the city would pay them back through savings realized due to a reduction in preterm deliveries, for example, or special-education diagnoses — both outcomes that have been linked to home visiting.

“These programs are expensive, but they have a high rate of return,” Nadeau said.

Research shows a range of positive impacts, including less isolation and depression for new mothers, fewer cases of child abuse and neglect, and increased financial stability for families.

A recent study by James Heckman, an economist and Nobel laureate at the University of Chicago, looked at a long-running program called the Nurse-Family Partnership and studied outcomes for children of more than 700 women in the Memphis area who participated in the early 1990s.

The study found that compared with a control group, children who received home visits had higher birth weights; better home environments, including more positive parenting attitudes, by age 2; and cognitive benefits by age 6. The effects were stronger and longer lasting for boys.

Researchers say the success of the programs comes from the highly personal approach, with support workers building trust with families over time, and also from the timing of the intervention, which starts during a critical window when parents are forming a bond with their children that can shape their long-term social and emotional health.

Sonia Palomo Figueroa became a family support worker at Mary’s Center after working for the Women, Infants, and Children nutrition assistance program in Maryland, educating mothers about nutrition. She found it was hard for mothers to focus on putting fresh fruits and vegetables on the table when they had much larger problems to worry about.

As a home visitor now with a program called Parents as Teachers, Palomo Figueroa said she can help struggling families more effectively because she can connect parents to a wider range of resources and help them address whatever challenges they have.

On a recent visit with Avelar De Andrade at her one-bedroom apartment in the District’s Brightwood neighborhood, Palomo Figueroa unfolded her “magic blanket” on the floor and opened a container of paints for 2-year-old David to play with. As he filled pages of construction paper, the women named the colors with him in English and Spanish, and Palomo Figueroa talked about how the activity was helping the toddler develop his hand-eye coordination and fine motor skills.

Recently, Avelar De Andrade’s daughter was diagnosed with a chromosomal disorder, and Palomo Figueroa helped the family learn more about it and found a support group of families in the area who are also affected by it. This week, Palomo Figueroa accompanied Avelar De Andrade to her daughter’s school to talk with a counselor about the disorder and how it can her affect her education.

Mary’s Center is one of the biggest providers of home visiting in the city, with the capacity to serve about 750 families a year.

The cost is about $4,500 per family annually for those meeting weekly. Visits can last for up to five years and tend to decline in frequency over time.

Citywide there are multiple home-visiting programs, including some that are more specialized: One focuses on father figures, another on parents with intellectual disabilities.

Diamond Holland, 26, was an unemployed single mother with a 4-month-old boy when she started meeting with a support worker every other week through a program called Healthy Families America, also run by Mary’s Center.

She was attracted by the promise of free diapers, she said, and a chance to learn more about how her son Artis was developing.

During the visits she also learned some useful tricks: how to soothe her baby when he was crying, for example, and how to set up a bedtime routine. The support worker helped her update her résumé and enroll in a training class she needed to secure a new job.

Now when her son learns a new word or she achieves a goal that she set, she gets excited to share the news during home visits.

“It feels like having a therapist in a way — in a good way,” Holland said. “It kind of releases my stress about the whole parenting thing.”